This study documents the history of the Tenth's formation at Fort Leavenworth, Kansas from 25 September 1866 to 5 August 1867. The study's focus is on the assignment of personnel, training of recruits, and the events surrounding the activation of the individual companies. An overview of the Black American military experience prior to 1866 summarizes military and related events to provide the context for the formation of the Tenth. A summary of the legislation that formed the Tenth is also included. In addition to the detailed chronology of events, the study documents the leadership and professional influence of Colonel Benjamin Grierson, the regimental commander. The study concludes that as a result of the regiment's formation at Leavenworth, the Tenth performed its first missions successfully, and subsequently helped to settle the West. The conclusion includes suggestions and areas for further study.