At the start of the
American Civil War, soldiers loyal to the
Confederate States of America took over U.S. Army posts in Texas, and Sutherland narrowly escaped capture. He made his way to
New York with other U.S. Army soldiers who had been stationed in Texas, and then received orders to take part in the expedition to garrison
Fort Pickens on
Santa Rosa Island near
Pensacola, Florida. Possession of this post was important to the war effort because it demonstrated that the
Union maintained a presence in the southern states while also contributing to the Union's effort to blockade the southern ports. Confederates unsuccessfully attempted to take the fort in 1861's
Battle of Santa Rosa Island, an engagement in which Sutherland was a participant. In April 1862, Sutherland was promoted to
major and assigned to
Fort Warren,
Massachusetts, where Union soldiers guarded Confederate prisoners of war. Later that year Sutherland traveled west, and was assigned as chief medical purveyor for
Union Army units in and around
Corinth, Mississippi. He subsequently established medical supply depots in
Columbus, Kentucky and
Memphis, Tennessee, followed by setting up army field hospitals in
Mississippi and
Tennessee, as well as a floating hospital on the
Mississippi River which was used by the
Army of the Tennessee during the
Vicksburg Campaign. During the
Siege of Vicksburg, Sutherland served on the staff of Army of the Tennessee commander
Ulysses S. Grant as assistant medical director and inspector of camps and transports. He took part in the
Battle of Jackson and the
Battle of Champion Hill, and was commended by Grant for effective medical support and efforts to improve camp hygiene, which caused the number of illnesses and deaths from
malaria,
smallpox and other diseases to be lower than had been the case in previous campaigns. After the fall of Vicksburg, Sutherland was assigned as medical director for the Department of Virginia and North Carolina, with responsibility for medical support to units in the field, five rear area general hospitals. In the spring of 1864, Sutherland was appointed chief medical purveyor for the
Army of the Potomac and the Army hospitals in and around
Washington, DC. His assignment was later expanded to included hospitals in and around
Annapolis, Maryland, and he remained in this position until the end of the war. Following the Confederate surrender, Sutherland was praised by the
Secretary of War for his successful acquisition, storage, and dissemination of more than $4 million in medical supplies and equipment (over $60 million in 2018). In 1865, he received brevet promotions to
lieutenant colonel and
colonel in recognition of the superior service he rendered throughout the war. ==Post-Civil War==