Shafter served as a 1st lieutenant the [[Quân đội Liên bang Miền Bắc]] [[7th Michigan Volunteer Infantry Regiment]] at the battles of [[Trận Ball's Bluff|Ball's Bluff]] andvà [[Trận Fair Oaks|Fair Oaks]]. HeÔng wasbị woundedthương at thetại [[Trận Fair Oaks]] andvà latersau receivedđó theđược Medalnhận ofHuy Honorchương forDanh heroismdự duringvì thehành battleđộng anh hùng khi chiến đấu. He led a charge on the first day of the battle and was wounded towards the close of that day's fighting. In order to stay with his regiment he concealed his wounds, fighting on the second day of the battle. On AugustNgày 22 tháng 8, 1862 he was mustered out of the volunteer service but returned to the field as major in the [[19th Michigan Volunteer Infantry Regiment]]. He was captured at the [[Trận Thompson's Station]] and spent 3 months in a [[Confederate States Army|Confederate]] prison. In April 1864 after his release he was appointed colonel of the 17th Regiment of [[United States Colored Troops|U.S. Colored Troops]] and led the regiment at the [[Trận Nashville]].
ByVào thecuối endcuộc of the warchiến, he hadông beenđược promotedthăng tolàm [[Brevet (military)|brevet]] [[Brigadier general (United States)|brigadier general of volunteers]]. He stayed in the [[Regular Army (United States)|regular army]] when the war ended. During his subsequent service in the [[Indian Wars]], he received his "Pecos Bill" nickname. He led the 24th Infantry, another [[United States Colored Troops]] regiment, in campaigns against the [[Cheyenne]], [[Comanche]], [[Kickapoo people|Kickapoo]] and [[Kiowa]] Indians in [[Texas]]. While commander of [[Fort Davis National Historic Site|Fort Davis]], he started a controversial court-martial of second lieutenant [[Henry Flipper]], the first black cadet to graduate from West Point. In May 1897 he was appointed as a [[Brigadier general (United States)|brigadier general]].
