Frederick

The Frederick or Fadrique family was a Catalan noble house founded by Alfonso Fadrique, the illegitimate eldest son of Frederick II of Sicily. Sent to Greece in 1317 as vicar general of the Catalan Duchy of Athens, he invaded Thessaly after 1318, took Neopatras and the lordship of Salona, and ruled as its first count until his death in 1338.

His sons divided his fiefs, with Peter inheriting Salona and James holding Siderokastron. James's son Louis Fadrique reunited much of the inheritance, served as vicar general of Athens and Neopatras from 1375 to 1381, and married the Byzantine princess Helena Kantakouzene.

When Louis died in 1382 his daughter Maria inherited Salona under her mother's regency, but in 1394 the town opened its gates to Sultan Bayezid I, ending the family's rule. The final Ottoman conquest followed in 1410.