From May through early July 1863, Vicksburg, Mississippi, a strategically important city on the Mississippi River, was besieged by Federal forces under the command of General Ulysses S. Grant, and by a flotilla of gunboats in the river commanded by Admiral David Porter. The city was surrounded by outlying Confederate lines of defense, but the Union forces also shelled the city itself, which was full of civilians, who dug caves into the clay hills of Vicksburg for protection from the artillery bombardment. The siege lasted 47 days, until the city and its Confederate defenders were at last starved into submission. The Confederate commander, Gen. John C. Pemberton, surrendered on July 4, 1863. So bitter were the feelings and memories of the people of Vicksburg afterward that they did not officially observe the Independence Day holiday for the next 81 years (not returning to its observance until 1945).
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