First Palaiologan Civil War

Byzantine civil war of 1321–1328
Part of the Byzantine Civil Wars
Byzantine Empire and surrounding territory in 1307, shortly before the First Palaiologan Civil War.
Date 1321 to 1328 Location Thrace, Macedonia and Constantinople Result Andronikos III becomes co-emperor and finally sole emperor.
Belligerents
Andronikos II Palaiologos Serbian Kingdom	Andronikos III Palaiologos Second Bulgarian Empire
Commanders and leaders
Andronikos II Syrgiannes Palaiologos	Andronikos III John Kantakouzenos, Theodore Synadenos, Syrgiannes Palaiologos
Strength
Unknown - Numerous Bulgarian, Serbian, and Tartar mercenaries, - Smaller number of supporters. - Population of Constantinople.	Unknown, - Numerous mercenaries - Younger nobility - Included more supporters, including non-combatants, - Population of Thrace and Macedonia.
Casualties and losses
First conflict (1321): unknown *Second conflict (1322): few, or light; *Third conflict (1327–28): possibly heavier, but comparatively light.	Unknown, but also possibly comparatively light

Andronikos II Palaiologos

Andronikos III Palaiologos

The Byzantine civil war of 1321–1328 was a series of conflicts fought in the 1320s between the Byzantine emperor Andronikos II Palaiologos and his grandson Andronikos III Palaiologos over control of the Byzantine Empire.

Michael IX was the son of Andronikos II, and was co-ruler and next in line for succession. He was also the father of Andronikos III and of another son named Manuel. In 1320, Andronikos III accidentally caused the death of his brother Manuel, after which their father died in his grief. The homicide and the general dissolute behavior of Andronikos III and his coterie, mostly the young scions of the great aristocratic clans of the Empire, resulted in a deep rift in the relations between young Andronikos and his grandfather.

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