Final answer:
The Mississippi River played a crucial role in the Union's strategy by allowing them to cut off Confederate supply lines and divide the Confederacy in half. Capturing Vicksburg was a major objective for the Union as it would secure complete control over the river. This control gave the Union a significant advantage in the war.
Step-by-step explanation:
The Mississippi River played a significant role in the Union's strategy during the Civil War. Controlling the river was crucial for the Union as it allowed them to cut off Confederate supply lines and divide the Confederacy in half. One major objective for the Union was to capture Vicksburg, a strategic location on the bluffs above the Mississippi River, as it would secure complete control over the river. By achieving this, the Union could control traffic and transportation on the river, giving them a significant advantage in the war.