Michael IX Palaiologos was Byzantine Emperor together with his father Andronikos II Palaiologos from 1294 until his death. Andronikos II and Michael IX ruled as equal co-rulers, both using the title autokrator.

Despite his military prestige, he suffered several defeats, for unclear reasons: his inability as a commander, the deplorable state of the Byzantine army or just simply bad luck. The only Palaiologan emperor to predecease his father, his premature death at age 43 was attributed in part to grief over the accidental murder of his younger son Manuel Palaiologos by retainers of his older son and later co-emperor Andronikos III Palaiologos.