The Ottoman Empire opened the overland trade route to the Orient through its empire following the fall of Constantinople in 1453. Their control over the Spice trade and heavy taxation led Europeans to seek alternative, oceanic trade routes.
The answer to your question is that it was the Ottoman Empire that opened the overland trade route to the Orient through its empire. After the fall of Constantinople in 1453, control of the known trade routes to the Orient, specifically those involving spices and other Asian goods, came under Muslim control. This breakthrough was a result of the strategic location and military strength of the Ottoman Empire. The Ottomans not only dominated the overland route but also took control of Red Sea ports in Egypt, further bolstering their command over the spice trade.
The establishment of these trade routes had significant implications. Given the heavy taxes imposed on goods travelling overland and the disapproval of doing business with Muslims prevalent among many Europeans, this led Europeans to seek alternative all-water, oceanic routes to South and East Asia, further sparking the Age of Discovery.
Thus, the Ottoman Empire was integral in controlling and establishing overland trade routes to the Orient, influencing the pattern of trade and exploration in the succeeding years.
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