"Frederick of Antioch (c. 1223 – 1255/6) was an Italian nobleman who served as the imperial vicar of Tuscany from 1246 to 1250. He was an illegitimate son of the Frederick II, Holy Roman Emperor, and an unidentified southern Italian noblewoman. He took part in the wars of the Guelphs and Ghibellines in northern Italy, and in the war over the Kingdom of Sicily following his father´s death (1250)." - (en.wikipedia.org 12.01.2020)
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