<P> Under McClellan and his eventual successor in the West, Maj. Gen. Henry Wager Halleck, the Mississippi became a somewhat neglected theater for operations in the West . Halleck, with McClellan's approval, believed in turning the enemy's Mississippi River strongholds rather than attacking them directly, so he moved away from the river . As he saw it, the Tennessee rather than the Mississippi was the "great strategic line of the Western campaign ." </P> <P> The Navy Department, however, remained committed to the idea of opening the Mississippi . The department, in the person of Assistant Secretary of the Navy Gustavus Vasa Fox, early decided on the capture of New Orleans by a naval expedition from the Gulf of Mexico, after which all other towns bordering the river would fall rather than face bombardment . The task of taking New Orleans was entrusted to Captain (later Admiral) David Glasgow Farragut, who followed his own plans for the battle; running his fleet past the forts that defended the city from the south on the night of April 24, 1862, he forced the city to surrender . After repairing his ships from the damage they had suffered while passing the forts, he sent them up the river, where they successively sought and obtained the surrender of Baton Rouge and Natchez . The string of easy conquests came to an end at Vicksburg, Mississippi, however, as the Confederate position there occupied bluffs high enough to render them impregnable to the naval gunnery of the day . </P> <P> Following the loss of Island No. 10 shortly before Farragut took New Orleans, the Confederates had abandoned Memphis, Tennessee, leaving only a small rear guard to conduct a delaying operation . In early June, this was swept aside by the gunboats of the Western Gunboat Flotilla (soon thereafter to be transformed into the Mississippi River Squadron) and a collection of War Department rams, and the Mississippi was open down to Vicksburg . Thus that city became the only point on the river not in Federal hands . </P> <P> Again, the Army under Halleck did not grasp the opportunity that was provided . He failed to send even a small body of troops to aid the ships, and soon Farragut was forced by falling water levels to withdraw his deep - draft vessels to the vicinity of New Orleans . The Army did not attempt to take Vicksburg until November, and then it was under the leadership of Maj. Gen. Ulysses S. Grant, after Halleck had been called to Washington to replace McClellan as General - in - Chief . </P>

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