Final answer:
The Byzantine Empire declined due to internal weaknesses, external threats, the Crusader sack of Constantinople, and the loss of important territories.
Step-by-step explanation:
The 4 biggest causes of the decline of the Byzantine Empire:
- Internal Weaknesses: The empire faced internal power struggles, economic instability, corruption, and a decline in military capacity.
- External Threats: The empire was constantly under attack from various external forces, such as the Seljuk Turks and the Ottoman Empire.
- Crusader Sack of Constantinople: The Fourth Crusade resulted in the sacking of Constantinople, causing significant damage to the empire's economy and infrastructure.
- Loss of Important Territories: The empire gradually lost key territories, including Anatolia, to Turkish invaders, diminishing its power and resources.
These factors together contributed to the decline and eventual fall of the Byzantine Empire.
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