Castel del Monte and the advent of the Angevins

The use of Castel del Monte as a prison, inaugurated by Manfred, son of Emperor Frederick II of Swabia, continued with the new Angevin dynasty, which in 1266 inherited the Frederickian castle network. Charles I of Anjou, understanding the strategic function of the castle for governing the territory and defending the kingdom, initially stationed a garrison consisting of a castellan and thirty soldiers, which increased to forty during the War of the Sicilian Vespers - one of the highest numbers among the castles of the Kingdom of Sicily - as documented by the Registers of the Angevin Chancellery. In the documents, in addition to management costs, after the Battle of Benevento on February 26, 1266, which marked the end of the Swabian dynasty, expenses for the transfer and maintenance of some illustrious prisoners are reported: among these, the sons of Manfred - Henry, Frederick, and Enzo (or Azzolino), imprisoned until 1299 - and Henry of Castile, detained from 1277 to 1291. A singular document from 1289, reports that the imprisoned Henry of Castile was periodically allowed to ride a mule around the perimeter of the castle.