Final answer:
The decline of the Byzantine Empire can be attributed to the loss of overseas territories and the decline of its economic position as a trading intermediary.
Step-by-step explanation:
The two main reasons for the decline of the Byzantine Empire were the loss of control over overseas territories and the decline of its economic position as a trading intermediary.
The empire lost control of southern Italy and Sicily, which had been important sources of trade and revenue. Islamic and Italian navies began to dominate trade in the Mediterranean, reducing the Byzantine Empire's economic influence.
Additionally, the empire's position as a trading intermediary between the Christian West and the Islamic world declined as direct trade between these regions increased.
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