Hromgla (mod. Rumkale, Turkey) was a fortress-town on a promontory above the Euphrates, 90 kilometers east of Edessa (mod. Şanlıurfa, Turkey) and 50 kilometers northwest of Aintab (mod. Gaziantep, Turkey). It was known as Ranculat by the Franks, Hromgla in Armenian, and Qal‘at al- Rûm in Arabic; all of these names derive from forms that mean “Castle of the Romans.”
Probably originally a Byzantine frontier fortress guarding a Roman road that ran along the Euphrates, Hromgla was settled by the Armenians in the eleventh century. At the time of the First Crusade (1096-1099), it was part of the principality of the Armenian Kogh Vasil (Basil the Robber), who was based at Kaysoun further north. It was in Frankish hands (probably of the counts of Marash) from at least 1116, when Count Baldwin II of Edessa captured its Armenian ruler. It survived the collapse of the county of Edessa (1144) and the death of Baldwin of Marash; in contrast to the other remaining Edessan fortresses, which were sold to the Byzantine emperor Manuel I Komnenos and then taken by the Saljûqs of Rûm or Nûr al-Dīn, Hromgla was given to the head of the Armenian church, the catholicos. It remained his headquarters, generally isolated from the rest of Armenian- held territory, until its capture in 1292 by the Mamlûks, who refortified and garrisoned it, changing its official name to Qal‘at al-Muslimûn (“Castle of the Muslims”). It is now ruined and partially flooded.