Why was an attack against Vicksburg by riv?

An attack against Vicksburg was crucial during the American Civil War because the city controlled a key section of the Mississippi River, which was vital for supply and transportation. The Union aimed to gain control of the river to split the Confederacy and enhance their strategic position. The successful siege of Vicksburg in 1863 by Union forces, led by General Ulysses S. Grant, ultimately accomplished this goal, giving the Union a significant advantage in the war.