The Battle of the Cyzicus (Catalan: Batalla del riu Cízic) was fought in October 1303 between the Catalan Company of the East under Roger de Flor, acting as mercenaries on behalf of the Byzantine Empire, and the Karasid Turks under Karesi Bey. The result was a crushing Catalan victory.
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Battle of the Cyzicus Wikipedia(Text) CC BY-SA