Isaac Doukas Vatatzes

Isaac Doukas Vatatzes (c. 1188–1261) was the elder brother of the Nicaean emperor John III Doukas Vatatzes and probably eldest son of the general Basil Vatatzes. He held the title of sebastokrator by 1253, and in 1261, as keeper of the imperial seal, witnessed the Treaty of Nymphaeum with Genoa.

Sent to Genoa to ratify it, he died during the negotiations and was buried in Genoa Cathedral. His short-lived son John married Eudokia Angelina and fathered Theodora, wife of Michael VIII Palaiologos.