Thomas Greely Stevenson was born on 3 February 1836 in Boston, Massachusetts. He joined the state militia as a private, advancing to the rank of major by the beginning of the War of Secession. On 3 December 1861, Stevenson was appointed colonel of the 24th Massachusetts Infantry. Stevenson and his regiment fought with Burnside's command in the battles of Roanoke Island and New Bern. With the arrival of Union reinforcements in North Carolina, he became a brigade commander in John G. Foster's division.
While most of the Union forces in North Carolina were sent to Virginia, Foster's command stayed. Stevenson's brigade participated in the Goldsborough Expedition in December 1862, tearing up railroad tracks and destroying the Goldsboro Bridge after a brief battle with Thomas L. Clingman's brigade. Stevenson was promoted to brigadier general of volunteers on 24 December 1862, and then held a series of quiet coastal postings in the Carolinas.
Stevenson next commanded the 3rd brigade in Alfred H. Terry's division in the siege of Charleston Harbor from July to September 1863. Stevenson remained in brigade command in the Charleston area until January 1864.
In April 1864, Stevenson was reunited with his old comrades in the Burnside Expedition when he given command of the 1st division of Burnside's IX Corps. Stevenson held a reputation as one of Burnside's best division commanders, fighting in the battles of the Wilderness and Spotsylvania Court House. During the latter battle, on 10 May, Burnside's corps had taken part in half-hearted fighting on Lee's eastern flank. Only Wilcox's division was in front of the IX Corps; Grant had missed an excellent opportunity to exploit Lee's vulnerable point. While resting beneath a tree, Stevenson was killed by a sniper's bullet. Stevenson was buried in Mount Auburn Cemetery in Cambridge, Massachusetts.