[1] Buell chose to defend the Union cause and entered the volunteer ranks of his birth state in 1861.

[2] Buell then led his regiment during the Battle of Stones River in late December into January 1863.

Gen. Milo S. Hascall's brigade when that officer was needed for division command, and Lt. Col. James T. Embree then led the 58th Indiana.

[5] On January 23, 1865, President Abraham Lincoln nominated Buell for appointment to the grade of brevet brigadier general of volunteers for his management of disassembled Federal pontoon trains[6] used to construct pontoon bridges over waterways, to rank from January 12, 1865, and the United States Senate confirmed the appointment on February 14, 1865.

Buell was appointed a brevet colonel in the regular army to rank from March 2, 1867, a reward for his performance in November 1863 at Missionary Ridge during the war.