The capture of Forts Henry and Donelson, and the Confederate surrender at the latter, were the first significant Union victories during the war and the start of a mostly successful campaign in the Western Theater. Ulysses S. Grant completed both actions by February 16, 1862, and by doing so, opened the Tennessee and Cumberland Rivers as Union supply lines and avenues of invasion to Tennessee, Mississippi, and eventually Georgia. The loss of control of these rivers was a significant strategic defeat for the Confederacy. This was the start of offensive actions by Grant that, with the sole exception of the Battle of Shiloh, would continue for the rest of the war.