Alexander graduated number one in his high school class in Helena and soon moved to Carrollton, Mississippi, to take a position as a teacher. In late 1880 he visited his uncle in Cincinnati, Ohio, and ended up remaining in that city. The next year, he enrolled at Oberlin College and attended that institution until passing the entrance examination for West Point in 1883. Alexander was sponsored by DemocraticU.S. Rep.George W. Geddes of Ohio.
Military career
During his term at West Point, Alexander was generally accepted by the other cadets and was not subjected to as much intolerance as previous black cadets. Alexander was known as an excellent student, especially in mathematics and languages and was a skilled boxer while at the academy. He graduated in the class of 1887 ranking 32nd in a class of 64.
Alexander was assigned to the 9th US Cavalry Regiment at Fort Robinson, Nebraska, which was an all-black regiment commanded by white officers and nicknamed Buffalo soldiers. In 1888, he was transferred to Fort Washakie, Wyoming, where he performed the garrison duty typical of an officer with a western frontier posting. While assigned to Fort Duchesne, Utah, in 1889, Alexander temporarily led the 9th Cavalry's B Troop, becoming the first black officer in the Army to hold a command position.[4]