Conradin (kŏn´rədĬn), 1252–68, duke of Swabia, titular king of Jerusalem and Sicily, the last legitimate Hohenstaufen, son of Holy Roman Emperor Conrad IV. While Conradin was still a child in Germany, his uncle Manfred made himself (1258) king of Sicily. When Manfred died the kingdom was seized (1266) by Charles I (Charles of Anjou). Young Conradin went to Italy in an attempt to recover his kingdom. Several cities rallied to his support, but he was defeated (1268) by Charles at Tagliacozzo. He was captured and executed at Naples.