By early 1862, a single general, Albert Sidney Johnston, commanded all the Confederate forces from Arkansas to the Cumberland Gap, but his forces were spread too thinly over a wide defensive line. Johnston's left flank was Polk, in Columbus with 12,000 men; his right flank was Brig. Gen. Simon Bolivar Buckner, in Bowling Green, Kentucky, with 4,000 men; the center consisted of two forts, Forts Henry and Donelson, under the command of Brig. Gen. Lloyd Tilghman, also with 4,000 men. Forts Henry and Donelson were the sole positions defending the important Tennessee and Cumberland Rivers, respectively. If these rivers were opened to Union military traffic, two direct invasion paths would lead into Tennessee and beyond.