Describe two factors that contributed to the fall of the Byzantine Empire.

The strength of the Byzantine Empire had been weakening for some time before its final collapse on May 29, 1453. For centuries, its empire had been picked apart by the Turks and other enemies. The emperors were finding it increasingly difficult to hold their fragile empire together. Here we will discuss two of the factors that led to its final fall.
A long series of civil wars
The fourteenth century was dominated by two costly civil wars that severely weakened the Byzantine Empire. The trouble started when Emperor Andronikos II excluded his grandson, Andronikos III, from succession. This resulted in his grandson revolting against him and then being crowned co-emperor. The two emperors constantly fought each other for the upper hand, forming alliances with different ethnic groups within the empire. This infighting greatly distracted the Byzantines from the real threat of the Turks, who continued to take over parts of the empire. More problems occurred in 1341 when Andronikos died, leaving it unclear who would succeed him. Fighting broke out between the regent John Cantacuzenus, supported by the aristocrats, and John V and the empress dowager, supported by the merchant class. The bloody and expensive civil war that followed left the empire in a very weakened condition.
The emergence of the Ottomans
Through the fourteenth century, the Ottoman Turks were a rising power in western Anatolia. They were able to gain much land when the Seljuk empire fell apart. The Ottomans saw Constantinople as a key territory in the expansion of their empire and began making preparations to take it from the weakened Byzantines when Mehmed II came to power in 1451. Emperor Constantine XI called on Western Europe for aid but very little came. The weakened and depopulated city was unable to fend off the Ottoman invasion that came in the spring of 1453. After a siege of fifty-three days, the Ottomans were able to breach the city's walls and take over the last remaining stronghold of the Byzantine Empire.
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