Fall of Constantinople

Constantinople was the capital of the Eastern Roman Empire, the Latin and the Ottoman Empires. It was founded in AD 330, at ancient Byzantium as the... new capital of the Roman Empire by Constantine I, after whom it was named. The city was the largest and wealthiest European city of the Middle Ages, and shared the glories of the Byzantine Empire, which was eventually reduced to the city and its environs. Although besieged on numerous occasions by various peoples, it was taken only in 1204 by the army of the Fourth Crusade, in 1261 by Michael VIII, and in 1453 by the Ottoman Sultan Mehmed II. An inner wall was erected by Constantine I, and the city was surrounded by a triple wall of fortifications, begun during the 5th century by Theodosius II. The city was built on seven hills as well as on the Bosporus, and thus presented an impregnable fortress enclosing magnificent palaces, domes and towers.
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The Byzantine–Ottoman Wars were a series of decisive conflicts between the Ottoman Turks and the Byzantine that led to the final destruction of... the Byzantine Empire and the rise of the Ottoman Empire. After the loss of Constantinople in 1204 the Byzantine Empire was left divided and in chaos; taking advantage of the situation the Sultanate of Rum began seizing territory in Western Asia Minor until the Nicaean Empire was able to repulse the Seljuk Turks against the remaining territories still under Greek rule. Eventually Constantinople was re-taken from the Latin Empire in 1261 by the Nicaean Empire. However the position of the Byzantine Empire in the European continent remained uncertain due to the presence of the rival kingdoms of the Despotate of Epirus, Serbia and the Second Bulgarian Empire. This, combined with the reduced power of the Sultanate of Rum led to the removal of troops from Asia Minor to maintain Byzantium's grip on Thrace. However the weakening of the Sultanate of Rum was by no means a blessing to the Empire as nobles known as ghazis began setting up their fiefdoms, at the expense of the Byzantine Empire.
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