In the meantime, the Union and Confederate armies accomplished little on the battlefield. The South failed to follow up on its victory at Bull Run, and for a full year very little fighting was actually done. The Union commander, George B. McClellan, was content to fortify his positions near Washington and to endlessly drill the volunteer regiments, even as Northern newspapers demanded action. The first Union victories took place in the west, where in February 1862 the newly commissioned Ulysses S. Grant captured Fort Henry and Fort Donelson in Tennessee. Grant then won the costly Battle of Shiloh, which prevented a Confederate campaign against Missouri and secured most of the Mississippi River valley, as far south as the fortified town of Vicksburg, Mississippi, for the Union. In April 1862 a fleet of Union gunboats under Commodore David Farragut sailed up the Mississippi River from the Gulf of Mexico...