|Benjamin Henry Grierson|
When the war erupted Grierson was still running the business in Meredosia. His military service began on May 8, 1861 as a volunteer aide-de-camp for Benjamin M. Prentiss. Prentiss commanded troops from Illinois operating in northern Missouri. Grierson served without pay initially with the nominal rank of lieutenant.
On October 24, 1861 he joined the 6th Illinois cavalry. The 6th was officially mustered into Federal service on November 19, 1861 with Grierson assigned as a staff officer. He was given the rank of major on January 9, 1862. He was promoted to colonel on March 28, 1862 and given command of the 6th. The 6th operated in west Tennessee and northern Mississippi. Grierson led the pursuit of Earl Van Dorn's forces after they raided the Union supply depot at Holly Springs, Mississippi.
|Union Cavalry Colonel Benjamin Grierson (seated with hand resting on chin) and staff.|
|Union Troops under the command of Colonel Benjamin Grierson at Camp Baton Rouge, May 1863.|
Following the war Grierson remained in the army with the rank of Colonel. He organized and was the first commander of the 10th US cavalry, one of the two cavalry units of black enlisted men with white officers that became known as Buffalo soldiers. He was brevetted brigadier general and major general in the regular army on 2 March 1867. He commanded Fort Riley, Kansas and Fort Gibson, Oklahoma from 1867 until 1869, heading the District of the Indian Territory from 1868 until 1869. After selecting the site for Fort Sill, Oklahoma in 1869 he supervised the construction and commanded the post until 1872. He then spent two years supervising recruiting efforts in St. Louis, Missouri. In the spring of 1875 he was sent to Fort Concho, Texas. He commanded the District of the Pecos from 1878 until 1880 during which period he is credited with opening West Texas to settlement and the railroads.
|Colonel Benjamin Grierson and Buffalo Bill with Chippewa and Souix Indians.|
In November 1888 he assumed command of the Department of Arizona. He was promoted to brigadier general on April 5, 1890 becoming one of the few civilians, no formal military training, to reach the rank. He retired on July 8, 1890.
He returned to Jacksonville, Illinois but made frequent trips to his ranch near Fort Concho. In 1807 he had a stroke from which he never completely recovered. He died August 31, 1911 at his summer home in Omena, Michigan.
|Grierson is buried at the Jacksonville East Cemetery, Morgan County, Illinois.|