A Latin eyewitness account of the Fourth Crusade (1202-1204), spanning the period from the preaching of the cross in France in 1198 to the division of spoils from the conquest of Constantinople (mod. Istanbul, Turkey) in April 1204.
The anonymous author of the Devastatio Constantinopolitana was probably a German cleric from the Rhineland; he developed the theme that the crusade was a series of broken contracts, in which the rich and mighty violated their vows, sold out the crusade, and betrayed the crusade rank and file. The work is rich in dates, names, numbers, and similar factual data, which are generally reliable but not invariably so. Its extraordinary perspective and wealth of detail make the Devastatio an important source of the second rank.