John II Doukas of Thessaly

John II Doukas (c. 1293–1318) ruled Thessaly from 1303 until his death. Succeeding his father Constantine Doukas young, he was given Guy II de la Roche of Athens as regent by the Thessalian magnates.

From 1306 the Catalan Company ravaged Thessaly for three years, but on coming of age in 1308 John rejected Athenian overlordship. Guy's successor Walter hired the Catalans against John, but they turned on Walter and killed him in 1311.

In 1315 he married Irene Palaiologina, an illegitimate daughter of Emperor Andronikos II, and drew closer to Byzantium. He died in 1318 without heirs, and the Catalans and local magnates divided his lands.