Alfonso Fadrique

Alfonso Fadrique (c. 1294–1338) was the eldest, illegitimate son of Frederick III of Sicily and Sibilla Sormella. In 1317 his father sent him to govern the Catalan Duchy of Athens as vicar general for his half-brother Manfred, but Manfred died before he landed, leaving another half-brother, William, as duke.

That year Alfonso married Marulla, daughter of Boniface of Verona, chief lord of Euboea, gaining rights to castles. He fought Venice and stormed Negroponte. When John II Ducas of Neopatras died in 1318, Alfonso invaded Thessaly, took Neopatras, Siderokastron and Pharsalus and styled himself its vicar general.

Relieved of his post in 1330, he received the counties of Malta and Gozo. He died in 1338, leaving five sons who founded the Fadrique house.