In February 1862, Union Gen. Ulysses S. Grant attacked Forts Henry and Donelson on the Tennessee and Cumberland Rivers to gain control of western Tennessee, Kentucky, and the rivers. After capturing Fort Henry on February 6, Grant approached Fort Donelson on February 14 as Flag Officer Andrew H. Foote's gunboats shelled the fort, but Confederate artillery drove off the ironclads. Confederate Gen. John B. Floyd then ordered a breakout for the next morning. On February 15, the attacking Confederate column under Gen. Gideon J. Pillow struck the Federal right wing under Gen. John A. McClernand and drove it back. At the center of the bent Union line stood the 11th Illinois Infantry, part of Gen. William H.L. Wallace's brigade and now commanded by Thomas E.G. Ransom. Facing superior numbers, short of ammunition, and under repeated assault, the regiment held its ground for five hours while trapped in crossfire from Confederate artillery and infantry. Wallace ordered his brigade to retreat and re-form, but the order did not reach the 11th Illinois. Col. Nathan B. Forrest's cavalry then hit the regiment in the rear and left flank. With Ransom wounded and the regiment isolated, its soldiers fought back to their own lines individually, and the last surviving member of the color guard carried the regimental colors from the field. The 11th Illinois lost 399 of its 500 soldiers, the highest casualties of any Union regiment engaged. The Confederate breakout ultimately failed, Federal forces counterattacked, part of Floyd's command escaped by boat on February 16, and the remainder surrendered to Grant on his demand for unconditional surrender.