Byzantine Civil War (1341–1347)

Timeline

1. 1341–1342Constantinople · Byzantine EmpireAfter Andronikos III died in June 1341, nine-year-old John V acceded. His mother Anna of Savoy and Patriarch John XIV Kalekas led the regency, sidelining grand domestic Kantakouzenos. The latter crowned himself in Thrace in October 1341, and the civil war formally began. The two sides controlled the capital and the Thrace–Macedonia heartland respectively, and sought external support from Serbia, Bulgaria, and Genoa.
2. 1342–1345Thrace–Macedonia · Byzantine EmpireBetween 1342 and 1345 the two sides fought repeatedly around Thrace, Macedonia, and Thessaloniki. Kantakouzenos brought in Ottoman reinforcements against the regency faction, while Serbian tsar Stefan Dušan also advanced south. In 1343 the regency faction allied with Dušan; in 1344 Kantakouzenos's daughter Theodora married Ottoman bey Orhan, deepening Byzantine reliance on Turkic military power and the frontier crisis.
3. 1346–1347Constantinople · Byzantine EmpireIn 1346 Kantakouzenos won a decisive victory near Adrianople, and in February 1347 entered Constantinople to co-rule as emperor with John V. Though the civil war ended, the treasury was exhausted, the population had drained away, and Ottoman penetration of Anatolia was irreversible, laying the groundwork for further territorial losses in the 1350s.