1. Internal Decline:
- Economic Weakness: Over time, the Byzantine economy weakened due to factors such as excessive taxation, corruption, and the loss of trade routes. This led to a decline in military strength and the ability to maintain a strong defense.
- Political Instability: The Byzantine Empire faced frequent political instability, with frequent changes in rulers, civil wars, and power struggles within the imperial court. These internal divisions weakened the empire and made it vulnerable to external threats.
2. Loss of Territories:
- Rise of Islam: The emergence of the Islamic Caliphates in the 7th century posed a significant challenge to the Byzantine Empire. The Muslims conquered vast territories, including Egypt, Syria, and North Africa, which had been under Byzantine control.
- Ottoman Expansion: The Ottoman Turks emerged as a powerful force in the 14th century and began expanding their territory into the Balkans. The Ottomans gradually chipped away at Byzantine territories, encroaching on the empire's heartland in Anatolia and eventually besieging Constantinople.
3. Fall of Constantinople:
- Siege of 1453: The final blow to the Byzantine Empire came with the Ottoman conquest of Constantinople in 1453. Under the leadership of Sultan Mehmed II, the Ottomans laid siege to the city, which had long served as the capital of the Byzantine Empire.
- Capture and Sack: After a two-month siege, the Ottomans breached the city's defenses and captured Constantinople. The city was sacked, and the last Byzantine emperor, Constantine XI Palaiologos, was killed in battle.
Following the fall of Constantinople, the Byzantine Empire effectively came to an end, and its remaining territories were absorbed into the Ottoman Empire.