Charioteers were the first great aggressors in human history. Aggression, by an opposite if not always equal reaction, stimulates defence, and so, before we consider how the charioteers and the horse-riding peoples who succeeded them altered the world in which civilised arts of peace had begun to flourish, we ought to examine the means by which the settled inhabitants of the rich lands sought to preserve what they had won from nature against theft and devastation.
The evidence from Jericho indicates that the very first agriculturalists were able to find the means to protect their dwellings against enemies, though who such enemies might have been remains obscure. Were they raiders who wished to plunder stored produce, perhaps on a regular, parasitic basis, or would-be agriculturalists who wanted Jericho’s fields and perpetual water-source for themselves, or mere vandals who threatened to plunder and destroy? The first seems the likeliest; people from the wilderness rarely want, let alone know how, to turn farmer and, while history is full of pointless vandalism, it more usually shows that raiders had the sense to see that parasitism profited better than rape and pillage. If that were the case at Jericho, we should probably see its walls and tower not simply as a refuge — the first of the three forms that fortification may take — but also as the second, a stronghold.
A stronghold is a place not merely of safety from attack but also of active defence, a centre where the defenders are secure from surprise or superior numbers, and also a base from which they may sally forth to hold predators at bay and to impose military control over the area in which their interests lie. There is a symbiosis between a stronghold and its surroundings. A refuge is a place of short-term safety, of value only against an enemy who lacks the means to linger in the vicinity or who operates a crude strategy of raiding against soft targets: the medieval villes perchées of south-eastern France, built on the summits of the precipitous coastal hills of Provence as sanctuaries against the visits of Muslim sea raiders, are perfect examples of the type.1 A stronghold, by contrast, must command an area productive enough to support a garrison in normal times but itself be sufficiently large and secure to house, supply and protect the garrison when under close attack. The builders of strongholds, therefore, have always had to make a nice judgement between the false economy of building too small and the extravagance of conceiving defences too expensive to be completed or, if completed, too extensive to be defended with the manpower available. The Crusader kingdoms, particularly in their years of decline, perpetually teetered on the brink of over-fortifying the shrinking garrisons that they could deploy.
Strongholds differ from refuges also in the features they must incorporate. It suffices if a refuge is strong enough to deter an attacker from the trouble of mounting an assault; ‘primitive warriors’, like the Maring inside their palisaded villages or the Maoris inside their hilltop pa, were safe from ‘routing’ or ‘raiding’ because their enemies lacked siege engines and had no means to support themselves for any length of time away from their own homes.2 Strongholds, typically the constructions of more advanced and therefore richer societies, must be able to withstand siege from attackers who bring their own rations or command a line of communications along which they can be supplied and who also deploy machinery. The circumference of a stronghold should therefore enclose a water-supply — especially if it is to be a protection for flocks — as well as storehouses and living-space.3 Above all, it must provide means for the garrison to wage an active defence — fighting-platforms that command a field of fire over prepared killing-grounds and strong gates through which counter-attacks can be mounted at moments of opportunity.
Until the coming of gunpowder, all attacks on strongholds had to be mounted at close range. That was true by definition of the simplest sort of attack — escalade — by which the besiegers sought to scramble over the walls with scaling-ladders, but also true of what siege engineers later called ‘deliberate siege’ — mining, battery with rams or projectile-throwers and counter-fortification with siege towers. Projectile-throwing, let it be said at once, rarely repaid the effort: a stout wall can easily absorb the energy directed against it by engines that depend on counter-weights or torsion springs to launch their missiles. Of their nature, moreover, such engines throw their projectiles at an inefficient angle of attack; the superiority of the gunpowder missile over all its predecessors was that, since it travelled in a flat trajectory, it could be directed at the one point where a high wall is vulnerable to collapse, at its foundations.
The designers of strongholds always sought, therefore, to deny an attacker easy access to a wall’s foundations and to provide the defenders with superior fire positions. One of the fascinations of Jericho is that its builders, in the dawn of fortification practice, appear to have perceived all the dangers by which it might be threatened and to have furnished it with protection against each. Thus the dry moat deprived the attackers of a platform from which to approach the walls’ foundations, while it also formed a prepared killing-ground (in an environment with impermeable soil, less evaporation and more water, it might have been made a wet moat). The walls, over three times the height of a man, required any attacker to bring scaling-ladders, a very insecure footing from which to launch an assault; it is likely that the walls were also furnished with fighting-platforms. Finally the tower, which overtopped the walls, gave the defenders a further advantage of height.
To these three defensive features — walls, moat, tower — fortification engineers were to add little in the 8000 years between the building of Jericho and the introduction of gunpowder. The principles were established; all subsequent improvements were no more than refinements of what Jericho’s builders conceived. Outer walls were to be set around inner ones — ‘multivallation’; obstacles were to be set at the lip of the moat (as they may indeed have been at Jericho, the evidence perhaps having perished); inner strongholds — ‘keeps’ or ‘citadels’ — were to be added and towers set on the outer rather than inner faces of the walls, to allow flanking fire; at very important sites, detached outworks — themselves strongholds in miniature — were to be built as a protection for gates or to deny points of advantage to an attacker. In general, however, it may be said that later fortification engineers made no greater improvement over Jericho than subsequent printers have over Gutenberg’s Bible.
Strongholds are a product of small or divided sovereignties; they proliferate when central authority has not been established or is struggling to secure itself or has broken down. Thus the Greek fortifications on the coasts of modern Turkey and Sicily were built to protect individual commercial settlements in the early years of colonisation; the castellation of England by the Normans — 900 castles may have been built between 1066 and 1154, varying in size between those that needed as few as a thousand and as many as 24,000 man-days for their construction — was undertaken as a deliberate means of enforcing Norman rule on the Anglo-Saxons;4 the Roman forts of the ‘Saxon Shore’, such as Reculver and Pevensey, were built to deny the estuaries of south-east England to Teutonic sea raiders emboldened by the decline of Roman power during the fourth century AD.5 More properly, however, we should regard the forts of the Saxon shore not as individual strongholds but as elements in the third form that fortifications may take: strategic defences. Strategic defences may be continuous, as Hadrian’s Wall was when kept in repair, or more commonly may comprise individual strongpoints so positioned as to be mutually supporting and to deny avenues of attack to an enemy across a wide front. Of their nature, strategic defences are the most expensive form of fortification to construct, to maintain and to garrison, and their existence is always a mark of the wealth and advanced political development of the people who build them.
The fortified cities of Sumer, once Sargon brought them under central control, may be seen as forming a strategic system, though they did so by the process of accretion, not design. The first deliberately conceived strategic system would appear to be that of the Nubian forts built by the pharaohs of the Twelfth Dynasty from 1991 BC onward. They eventually stretched for 250 miles along the Nile, between the First and Fourth Cataracts, constructed so as to command both the river and the desert and at distances from each other which allowed intercommunication, perhaps by smoke signals. Again, the archaeological evidence reveals a concept of fortification to which subsequent builders of strategic defences found little to add. The early forts, located in a region around the First Cataract where the valley is wide enough to support an agricultural population, were designed to protect it as well as dominate the river. The later forts, which followed the line of the Egyptian advance into barbarous Nubia and the much narrower upper Nile, were more strictly military in function. Surviving written records reveal that the upstream forts were conceived as a truly military frontier. Senusret III erected a statue of himself and raised an inscription: ‘I have made my boundary, having sailed further south than my fathers. I have increased what was bequeathed to me. As for any son of mine who shall maintain this boundary … he is a son of mine who was born to My Majesty … But as for whoever shall abandon it, and who shall not fight for it, he is no son of mine.’ The inscription was found at the fort of Semna and dates from 1820 BC. The statue has been lost but in the same fort has been found a cult statue of Senusret III which dates from 1479–26, clear evidence that his admonition to hold what he had won had been taken to heart.6
Egyptian frontier policy in Nubia was a model for later imperialists everywhere. At Semna three forts are situated so as to control the river from both banks, and there are tunnels so that water can be drawn from it; a mud-brick wall protected the road to the south on the landward side for several miles. All the forts contain large granaries, two sufficient to supply several hundred men for a year; they were probably restocked from the rear supply centre at Askut, an island fortress apparently purpose-built as a grain store. Another inscription reveals what the garrison’s duties were: ‘to prevent any Nubian from passing … when faring northward, whether on foot or by boat, as well as any cattle of the Nubians. An exception is a Nubian who shall come to barter at Iken, or one with an official message.’ Forward of the forts, the Egyptians maintained a desert patrol recruited from Nubian desert men, named Medjay. (Among the ‘Semna Despatches’ found on papyrus at Thebes is a typical desert patrol report: ‘The patrol which set out to patrol the desert edge … has returned and reported to me as follows: “We have found a track of 32 men and 3 donkeys.” ’) British officers with experience on India’s North-West Frontier would recognise Egyptian practice instantly. Like the Egyptians, the British maintained an administered zone where large garrisons protected the settled population, a forward zone where the garrisons held purely military forts, and forward of that again a ‘tribal’ zone where only the roads were defended and the surrounding areas were policed by tribal militias — Khyber Rifles, Tochi Scouts — recruited from the peoples against whom the whole elaborate defensive structure had been erected in the first place.
It is not surprising that the plans of both Jericho and the Second Cataract forts perpetuated and reproduced themselves over time and distance; it is not even very surprising that they emerged so early. Given that man turns his mind to integrating the various but limited elements of architecture and town-planning into a system of self-protection, it almost inevitably follows that something like Jericho or the Semna complex will emerge; similarly, though this has psychological rather than material roots, the practice of turning poachers into gamekeepers — Medjay, Khyber Rifles — follows almost immediately from the recognition that primary control of a frontier between civilisation and barbary is best exercised by bribing those who live on the wrong side of it.
It would be wrong to surmise, however, that the principles that underlay the construction of Jericho and Semna were rapidly or widely disseminated. The people of Jericho were rich in their time, the pharaohs of the Twelfth Dynasty richer still. Elsewhere mankind remained poor and thinly settled until well into the second millennium BC and it is only in the first millennium that defended settlements came to be built over a wide area. Archaeologists have noted the appearance of a fortified Greek settlement at Old Smyrna, within a defensive wall furnished with cut-stone bastions, in the ninth century BC, and of walled settlements at such widely distant spots as Saragossa, Spain, and Biskupin, Poland, in the sixth century.7 Hilltop enclosures — the ‘Iron Age forts’ so familiar in Britain, where 2000 have been identified — may have been dug in south-eastern Europe as early as the third millennium, but it was only in the first that they became widespread.8 Historians continue to disagree about their function — proto-towns or places of temporary refuge? — and about the political conditions that prompted their building. The probability is that, like the Maori pa, they were the products of a society that had become tribalised and in which neighbouring groups sought to secure their movable goods against raiding; but we cannot be sure. All we know is that fortification spread from south-east into north-west Europe during the first millennium, matched by the establishment of defended ports along the coasts of the Mediterranean and the Black Sea as Greeks and Phoenicians voyaged to establish trading colonies beyond their homelands. Fortification undoubtedly followed trade; indeed Stuart Piggott, the leading expert on urban prehistory, suggests the existence of a major two-way trade route leading from the fortified Mediterranean coastal ports to the inland hill-forts of France and Germany, along which passed wine, silk, ivory (and even apes and peacocks — a Barbary ape reached a king of Ulster in prehistoric times) on the northward leg, and amber, furs, hides, salt meat and slaves in return.9
By the end of the first millennium fortifications pimpled the face of the temperate zone. In China, where the first towns had been unwalled and where, in the treeless loess plains even the basic materials are lacking, towns walled with beaten earth (pisé) nevertheless appeared during the Shang dynasty (c. 1500–1000 BC), which exercised the earliest centralised authority; interestingly, the Shang ideograph for a city, yi, incorporates the symbols for an enclosure and a man kneeling in submission, suggesting that, as was often the case elsewhere, the fort in China was an institution of social control as well as of defence.10 In historic Greece, following the Dark Ages brought on by the collapse of Minoan civilisation, the emergent city states walled themselves as a matter of course; so too did those in contemporary Italy, including, of course, Rome. By the time Alexander the Great set off on his march of conquest through Persia to India in the fourth century BC, strategists expected to find their path blocked by strongholds whenever they campaigned in settled terrain.
Carl von Clausewitz (1780–1831), Prussian general and military thinker. His book On War has largely determined how the Western world has thought about warfare since his death.
Toppled idols on Easter Island, whose Polynesian inhabitants destroyed their own civilisation by warfare before the coming of the European voyagers.
A Mameluke warrior of the Fourteenth Century AD practising the exercises of the furusiyya, the most refined form of the steppe horseman’s skill-at-arms.
An image d’Epinal of the Mamelukes of Egypt in combat with Napoleon’s troops at the battle of the Pyramids, 1798. Furusiyya individualism was defeated by drilled musketry.
Zulu warriors charging with the stabbing assegai in the war of 1879. After their victory at Isandhwlana they were destroyed by British firepower.
A Partisan’s Mother, S. Gerasimov, 1943. This heroine of Socialist Realism defies the Nazi invader with a future partisan in her arms.
Japanese swordsmen and the art of the duel. The cult of the sword in Japan held the gunpowder revolution at bay until the Nineteenth Century.
A Mark IV Panzer of the Afrika Korps in the battle of El Agheila, April 1941. Free movement in the open desert was limited by logistics.
Mountain infantry of the Austro-Hungarian army scaling a peak in the Julian Alps. There was prolonged fighting in these ranges and in the Carpathians and Vosges in 1914–18.
German infantrymen manhandling a staff car across the roadless steppe in spring, 1942. The seasonal rasputitsa halts military movement in western Russia twice each year.
A future Yanomamö warrior. His weapon is a ‘simple’ bow which has not developed from its Stone Age origins.
A New Stone Age hunting scene from Alpéra, southern Spain. The bow may have appeared as a weapon about 12000 BC.
Egyptian archers from the tomb of Mesehti at Assiut, Middle Kingdom (1938– c. 1600 BC). Their lack of bodily protection indicates the tentative nature of early Egyptian warfare.
The Assyrian victors of the Chaldean campaign (late Seventh Century BC) counting heads. This was not a ritual but evidence of a new ruthlessness in war-making.
Aztec warriors in battle gear, as depicted by native artists in the Lienzo de Tlaxcala after the Conquest. Their feathered headbands indicate prowess in combat.
Sethos (Seti) I in battle with the Libyans at Karnak, Fourteenth Century BC. The coming of the chariot brought a novel intensity to Egyptian warfare.
The Palette of Narmer (Menes) shows the unifier of Lower and Upper Egypt, reckoned the first pharaoh (c. 3100 BC), despatching a captive.
Rameses II, in a similar pose seventeen centuries later, despatches a Nubian. Ritual slaughter may have been a feature of Egyptian, as of Aztec, warfare.
Assyrians hunting the large-horned ox from a chariot, Seventh Century BC. The chariot may originally have been developed for hunting.
The Standard of Ur, from the Sumerian kingdom, about 2500 BC. The war cart is drawn by onagers, not horses, and the warriors are wearing proto-armour.
Mounted Assyrian warriors of the reign of Shalmaneser III (858–24 BC). They ride without saddles and have not yet learnt the forward seat.
Assyrians in battle with Arabs, c. 650 BC. The Arabs are riding the recently domesticated camel, while the Assyrian archers now ride from the forward ‘control’ position.
A Sarmatian mounted warrior, kin to the Scythians who were enemies of Rome and Persia. His scale-armour points the way to the development of mail and plate.
Alexander the Great confronts Darius at the battle of Issus, 333 BC. The Persian emperor in his chariot flies from Alexander on Bucephalus in a graphic symbolisation of the cavalry revolution.
Iranian horsemen of the steppe, first millennium BC. Their elaborate horse-furniture indicates their mastery of their mounts, whose slender Caspian build anticipates that of the Arab horse.
The coming of the stirrup: mounted warriors of the Carolingian empire, from the St Gall Psalter, couch lances for the charge.
The walls of Jericho, excavated in 1956, which have been dated to 7000 BC. The fortifications also include a rock-cut dry moat and tower.
The Great Wall of China near Peking, in its reconstructed state. A strategic defence, it was constantly extended to protect the empire from the steppe nomads.
Hadrian’s Wall at its centre near Cuddy’s Crags. Begun in 122 AD, it is the best-preserved of the frontier fortifications of the Roman Empire.
Porchester Castle, a Norman stone-built keep inside a Roman fort of the Saxon Shore, one of the Empire’s major defensive systems.
Krak des Chevaliers, greatest of Crusader castles. The problem of the Christian knights was to find the garrisons for the strongholds they built.
The siege of Limerick, 1691; the plan shows ‘artillery’ bastions added to a mediaeval wall with towers, and the besiegers’ approaches, parallels and star earthworks. My Bridgman ancestors were given land nearby for service in this siege.
Warriors: the Zouave in the foreground is a Frenchman wearing the dress of a North African tribe, tribute to the reputation of ‘primitive warriors’ among Nineteenth-Century European armies.
Slave soldiers: Janissaries (‘new soldiers’) of the Ottoman Empire parading at Lake Van in the Sixteenth Century; Janissaries were enslaved by the Sultan from Christian children of the Balkans.
Militia: Swiss citizen soldiers on parade. Switzerland continues to make the performance of military service a condition — for males — of the enjoyment of electoral rights.
Mercenary: John Hawkwood, painted by Uccello in 1436, the English commander of the White Company, who sold his services to Florence, Milan and the papacy in the Fourteenth Century.
Regular: The Village Recruit, after Wilkie; drink, flattery and the King’s shilling tempt a landless labourer into long service in George III’s army.
Conscript: Londoners line up to register for compulsory military service at King’s Cross, May, 1939, on the eve of the Second World War.
The general principle held, however, that a multiplicity of strongholds indicated a weakness or absence of central authority. Alexander conducted at least twenty sieges between 335 and 325 but none within the confines of the Persian empire; as befitted a great state, its interior was defended at its periphery. Alexander’s three battles with the Persian army, at the Granicus, Issus and Gaugamela, were fought in open country. It was only when he had subdued Persia and pushed on into the fractious lands between it and India that he had to revert to the siegecraft he had practised when breaking into the empire during 334–2. The Romans conducted one siege after another when building their empire, from Agrigentum — one of the early fortified ports of Sicily — during the First Punic War in 262 BC to Alesia, a gigantic Celtic hill-fort, where Caesar overthrew Vercingetorix in 52 BC. They also, in the course of their advance from the Alps to Scotland and the Rhine, dotted the landscape with the rectangular legionary forts that their soldiers were trained to throw up at the end of each day’s march in hostile territory. These standardised designs — with their four gates and central ceremonial square they strangely resemble the classical Chinese city — also formed the model for the principal Roman cities of conquest: under the modern centres of London, Cologne and Vienna lie the remains of the square legionary forts on which they all grew up.
Within the pacified Roman empire, however, the conquerors did not fortify: ‘the majority of Gallic cities developed as open settlements and were left undefended’.11 That was what was meant by pax Romana — open cities, safe roads, the absence of internal boundaries over the great extent of western Europe. It was assured by fortification elsewhere, of course, though exactly how remains one of the most contentious issues in the writing of Roman history. The physical evidence of fortification at the frontiers is there for all to see, most visibly in the central stretches of Hadrian’s Wall. Traces of the Antonine Wall, by which the Romans marked an even deeper advance into north Britain, are still detectable, as are parts of the limes along the Rhine and the Danube, the fossatum Africae on the desert edge in Morocco, Algeria, Tunisia and Libya and the limes Syriae, which stretched from the Gulf of Aqaba and the north of the Red Sea to the headwaters of the Euphrates and Tigris. Were these ‘scientific frontiers’, as some modern historians think, or merely marks of the limits of effective control established by Roman armies campaigning to pre-empt the forces of disorder, some merely local, some strategically threatening, which they met at the effective economic boundaries of the Mediterranean world? Edward Luttwak, in his The Grand Strategy of the Roman Empire, has successfully propagated the belief that the Romans, like the British in India, firmly conceived a scheme of what could and could not be defended, though varying the method by which it was defended in practice — strong central army first, then strong local defence, finally an unsatisfactory mixture of the two — as their fortunes dictated.12 Luttwak’s opponents deny any such consistency, particularly where the eastern frontiers were concerned. Benjamin Isaac believes that Rome sustained an aggressive policy against Persia and Parthia over a very long period, and that the fortifications in the east should therefore be seen as defended lines of communication for expeditionary armies; C.R. Whittaker thinks that there were permanent local troubles on many frontiers and that Roman defences, like those of the Egyptians in Nubia or the French in Algeria during the war of 1954–62 (the Morice Line), were principally intended to keep malefactors at arm’s length from peaceful cultivators.13
What is certain is that the growth of central authority was almost everywhere and at all times marked by the construction of strategic defences, from those as simple as Offa’s Dyke between Anglo-Saxon England and Celtic Wales — though a mighty undertaking it must have been in its time, consuming tens of thousands of man-digging days — to the still-unravelled complexities of the Great Wall of China. The exact function of such defences is more difficult to define, varying so much as to defy generalisation. Thus the Habsburg Military Frontier with the Ottoman lands — the krajina — was certainly meant to keep the Turks out; but building it was a tribute more to Turkish strength than to that of Austria, though the Habsburgs were the older dynasty. By contrast, the chain of fortresses erected at great expense to protect the British ports on the south and east coasts in the 1860s (seventy-six were completed or under construction by 1867) was a response to a phantom threat from France, perhaps evidence of a neurotic distrust of the power of ironclad warships to supply the defence which the English had always confidently expected from wooden walls.14 Louis XIV’s chain of fortresses along the eastern border of France was an aggressive device, designed to extend French power step-by-step into the Habsburg lands; even more so was the cherta, a line of improvised fortifications pushed eastward by the tsars from the sixteenth century on into the wild lands of the steppe, intended to press the nomads south of the Ural mountains and to open a path of settlement into Siberia. The cherta could only be extended, however, with the half-willing assistance of the Cossacks, and one of its functions, which they were slow to perceive, was that of bringing their free settlements under Muscovite control.15
That prescription — half defensive, half oppressive — describes, in the view of Owen Lattimore, who with Frederick Jackson Turner was the greatest of frontier historians, the role of China’s Great Wall. Turner, in a famous paper of 1893 to the American Historical Association, argued that the idea of the moving frontier, which offered free land to anyone prepared to venture westward, had been decisive in shaping the American national character — exuberant, energetic and inquisitive — and in assuring that the United States would remain a great democracy. Lattimore, by contrast, represented the Great Wall as a different sort of frontier in every way. Admittedly it moved: beginning by the interconnection of a number of local walls, raised by regional rulers to protect their embryo states, its line was eventually fixed along the boundary between the soils of irrigated agriculture and those of pastoralism — roughly river valley and steppe — by the Chin dynasty in the third century BC. Neither they, however, nor any subsequent dynasty, in Lattimore’s view, could get the line of the Great Wall right: sometimes it pushed northward to enclose the Ordos plateau in the great bend of the Yellow River, sometimes that was abandoned, while there were numerous extensions to and realignments of its western end where it reached out toward the Tibetan plateau; eventually all its arms and branches ran to a total length of nearly 4000 miles.16 Lattimore argues that all these twists and turns are evidence less of the waning or waxing power of dynasties than of the pursuit of a chimera. Successive emperors did indeed seek a ‘scientific’ frontier, on the line where land suitable for peasant farming met that which ought to be abandoned to the herding nomads. No such line, however, was to be found, since the two zones were not only separated by one of mixed ecology, but that third zone itself shifted with changes of climate — desiccation, humidification — in the interior of the great Eurasian land mass. Attempts to dictate ecology by colonising the border zone with peasant Chinese produced a Schlimmbesserung — worsening by improvement. The settlers, particularly those implanted in the great bend of the Yellow River, tended to nomadise themselves when desiccation set in and thus to swell the numbers of the horse peoples who beat in successive waves against the Wall; offensives by the horse peoples also undid the efforts of the frontier commanders to sinicise the semi-nomads whose natural home the inter-zone was.17
It was not surprising, in the circumstances, that the Chinese never unwalled the cities around which their irrigated settlements had first grown up. In times of dynastic strength they served as centres of imperial administration; during periods of turmoil, brought on by nomadic assaults on the throne, they remained sanctuaries of the imperial tradition which always reasserted itself to tame and sinicise the conquerors. City walls were rightly regarded as symbols of civilisation — under the Ming (AD 1368–1644) 500 were completely reconstructed — as was the Great Wall itself.18 Both, however, were no more than props to the imperial system, whose ultimate strength reposed in the philosophical beliefs of the Chinese about how society should properly be ordered. Such beliefs could retain their force not so much because they permeated society from top to bottom — they tended to remain the cultural property of the land-owning and official class — as because the numbers of outsiders who succeeded to power were comparatively small, and came from steppe societies which, to an extent that they themselves did not often recognise, had themselves been subtly sinicised by sustained contact with the target civilisation at its fortified edge. In that sense, the Great Wall was itself a civilising instrument, a diaphragm through which potent ideas flowed outward to moderate the barbarism of those who beat perpetually at the gates.
The classical civilisation of the West was not so lucky. Unlike the Chinese, the Romans were assaulted by a sustained surge of barbarians in very large numbers, too few of whom had been romanised by continuous and mediating contact with civilisation to ensure its preservation. From the middle of the third century AD, as barbarian raiders struck more frequently and deeply into Gaul, provincial officials began to wall inland towns; even by the fifth century, however, only forty-eight cities had been fortified, mostly in frontier or coastal areas; in Spain only twelve had been walled, while in Italy south of the Po valley Rome alone retained its defences.19 Chains of forts were thrown up along the North Sea, Channel and Atlantic coasts, and the limes down the Rhine and Danube were strengthened. Once these frontier defences were overrun, the western empire lay ripe for the taking. The barbarian kingdoms that succeeded to Rome did not at first need, even had they known how, to fortify. Successive irruptions by wholly unromanised intruders — Scandinavian sea raiders, Arabs, Central Asian steppe peoples — met no strategic defences to bar the way and few internal fortifications. Little wonder that Charlemagne’s brave effort to recreate a pan-European state was whittled away piecemeal by their assaults.
Eventually western Europe was re-fortified, but in a pattern that would have rightly caused a Chinese dynasty nothing but alarm. The mysterious revival of trade between 1100 and 1300, itself perhaps due to an equally mysterious rise in the European population from about 40,000,000 to about 60,000,000, in turn revived the life of towns, which through the growth of a money economy won the funds to protect themselves from dangers beyond the walls; Pisa, for example, surrounded itself by a ditch dug in two months in 1155 and completed a continuous wall with towers the following year. The newly walled towns, however, used their immunity not to underpin royal authority but to demand rights and freedoms; Pisa was walled as an act of defiance against the emperor Frederick Barbarossa.20 Meanwhile, in a process the Chinese emperors would have found even more alarming, local strongmen were busily covering the face of western Europe with castles, at first simple entrenchments, then from the tenth century onward more dominating mottes, finally true stone strongholds. Some of these places were owned by a king or his trusted vassals, but progressively the majority must be classified as the illegal (‘adulterine’) creations of the disobedient or upstart. Their justification was always that threats from the ungodly — Vikings or Avars or Magyars — required them to have a secure place in which to stable their warhorses and house their men-at-arms. The reality was that, in a Europe which lacked both strategic defences and strong central authorities, they were profiting from circumstances to make themselves local overlords.
Castellation on such a scale — there were three castles in the Poitou region of France before the Vikings began to raid, thirty-nine by the eleventh century; none in Maine before the tenth century, sixty-two by 1100; and the pattern repeats itself elsewhere — eventually cancelled out the advantage it gave in local struggles for power.21 When every strong man kept his court armed, the result was not overlordship, and mutual support of central authority against intruders even less, but endemic local warfare. Kings issued licences for castles and, with their great vassals, overthrew the adulterine whenever they could. Castles, however, could be built very quickly — a hundred men might throw up a small motte in ten days — but a castle once built was much more difficult to reduce if its castellan dug in his heels.22 The strength of castles greatly exceeded the force of siegecraft, a truth not to be overturned until the coming of gunpowder and that had held good since the building of Jericho.
Ancient historians are fascinated by the representations of siege practices and siege engines that excavations in Mesopotamia and Egypt have revealed — battering-rams, scaling-ladders, siege towers, mineshafts. Written accounts of Greek siege warfare disclose the appearance of the catapult, earliest of projectile-throwers, in 398–7 BC.23 The earliest representation of a ram — of very flimsy type, though apparently protected by a roof — is from Egypt and dated to 1900 BC; the scaling-ladder was depicted about 500 years earlier. A much more formidable battering-ram, mounted in a wheeled carapace, is shown in a palace relief sculpture from Mesopotamia of about 883–59 BC, together with a scene of engineers undermining a wall. A mobile siege tower, also Mesopotamian, is shown in another relief dated to 745–27 BC, by which time the construction of ramps to fill a moat and reach the crest of the wall had also been brought into use; large siege-shields, to protect archers shooting at the defenders on the parapet, were apparently also by that time an item of siegecraft. There are also allusions to the use of fire to attack gates, and possibly also the interior of a fortification, while interruptions of the water supply, where practicable, and, of course, starvation had become standard siege techniques.24
All the works of siegecraft available to commanders before the invention of gunpowder were, therefore, devised between 2400 and 397 BC. None, except starvation, offered a certain, or even very effective, means of bringing a fortification to surrender. A besieger’s best hope of a quick result, according to the classical strategist Polybius, lay in exploiting the defenders’ complacency or achieving surprise. Treachery was another device — it brought the fall of Antioch to the Crusaders in 1098, for example, and that of many other strongholds as well.25 Those methods apart, an attacker might sit for months outside the walls, unless he could find a weak spot or create one himself. Chateau-Gaillard was taken in 1204 through an unguarded latrine tunnel; Rochester, on the other hand, besieged by King John in 1215, lost the southern corner of its keep to undermining and the firing of the tunnel timbers — which consumed the fat of forty bacon pigs — but was eventually taken only because the garrison had run out of food after fifty days of continuous investment, the greatest siege in England up to that time and for long after.26
The taking of Jerusalem by the Crusaders in 1099 with a siege tower was an exceptional event, ascribed in part to the weakness of the garrison, in part to the religious inspiration of the attackers. In general, the advantage in siege warfare before gunpowder always lay with the defender, as long as he took the precaution of laying in supplies, and to such an extent that it was a convention of siege warfare in the medieval West for the parties to agree on a time limit, at the expiry of which, if the siege had not been raised by a relieving force, those inside the walls were allowed to march out without penalty.27 Since the attackers might themselves run out of food, or even more probably succumb to disease in their unhealthy encampments, such an agreement was a sensible option for any garrison.
We ought, therefore, to treat with extreme reserve all representations of siegecraft and siege engines, if offered as evidence of their importance in ‘the art of war’ at any time before the gunpowder age. Warfare in art always calls forth from the artist the representation of the potential and the sensational, rather than that of documentary realities; in that light, Egyptian and Assyrian wall-paintings and sculpture reliefs of royal triumphs under the walls of cities are no more to be relied upon as testimony of contemporary actualities than the heroic portraits of Napoleon by David and Le Gros are to be taken as depictions of his behaviour as a general in the field; between war art and the war comic interposes a very narrow gap, and probably has done so since the first court painter was commissioned to paint the first king-conqueror. Fortifications, and all actions to bring them low, are a ready subject for the war artist, whose misrepresentation of what passed between defender and attacker may well have imposed a grave distortion on our understanding of defensive warfare in the pre-gunpowder age.
The subject of fortification may be left with these thoughts in mind: stoutly defended and well provisioned strongholds were difficult to take at all times before the gunpowder age; such strongholds were often as much instruments of defiance of central authority — or, a subject to be explored later, a means to overawe free citizens or cultivators — as components of a strategic defence; strategic defences, never easy to align with natural frontiers and always costly to build, maintain, provision and garrison, ultimately depend for their strength on the will and the capabilities of the power they were conceived to defend. ‘They labour in vain who build’ defences that are expected to stand by themselves.