When did the Byzantine Empire end?
Decline of the Byzantine Empire
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Following the death of Andronikos III in 1341, another civil war broke out which was to continue until 1347. When Andronikos III died he left his six-year-old son under the regency of Anne of Savoy. The de facto leader of the empire, John Cantacuzenus, who was not only a close associate of the deceased emperor but an extremely wealthy landowner, wanted to become regent.[15] However, things did not go his way and he was declared emperor in Thrace.[16] This conflict had elements of class warfare, in that the rich supported Cantacuzenus while the poorer folk supported the empress regent. The civil war of 1341–1347 saw exploitation of the Byzantine Empire by the Serbs, whose ruler took advantage of the chaos to proclaim himself emperor of the Serbs and Greeks. The Serbian king Stefan Uroš IV Dušan made significant territorial gains in Byzantine Macedonia in 1345 and conquered large swathes of Thessaly and Epirus in 1348.[17] Although Dusan would die along with his dream of a Serbian Greek empire in 1355,[18] Byzantium would still face a powerful Turkish state across the Sea of Marmara. Luckily for Cantacuzenus, he conquered Constantinople in 1347 and ended the civil war afterwards.[19] In order to secure his authority during the civil war, Cantacuzenus hired Turkish mercenaries. Although these mercenaries were of some use, in 1352 they seized Gallipoli from the Byzantines.[18] Although in 1354 the rogue mercenaries were defeated by western crusaders,[20] Turkish armies would eventually control many of the Byzantine Empire's once-held territories. These two monumental civil wars severely diminished the Byzantine Empire's military strength and allowed its opportunistic enemies to make substantial gains into Byzantine territory.