In July 1866, Miles was appointed a colonel in the Regular Army, confirmed by the
U.S. Senate. The next year, in April 1867, he was appointed assistant commissioner of the North Carolina branch of the
United States War Department's Bureau of Refugees, Freedmen, and Abandoned Lands, (
Freedmen's Bureau), serving under Bureau Commissioner,
Brigadier General Oliver O. Howard (1830–1909). On June 30, 1868, he married Mary Hoyt Sherman (daughter of
Charles Taylor Sherman, niece of fellow
Union Army General
William T. Sherman and
U.S. Senator John Sherman, and granddaughter of
Charles R. Sherman). Miles played a leading role in nearly all of the
U.S. Army's campaigns of the later
American Indian Wars against the native
American Indian tribes of the
Great Plains, of the
Mid-West, among whom he was known as "Bearcoat" (for his characteristic bearskin fur coat). In 1874–1875, he was a field commander in the force that defeated the
Kiowa,
Comanche, and the
Southern Cheyenne along the upper
Red River of the South. Between 1876 and 1877, he participated in the campaign that scoured the Northern Plains after 5 companies of the
7th U.S. Cavalry Regiment under the command of Lt. Col.
George Armstrong Custer were killed at the
Battle of the Little Big Horn in June 1876, and forced most the
Lakota Sioux tribe and their native allies onto designated federal
Indian reservations. In the winter of
1877, he drove his bluecoat mounted troops on a forced march across the eastern
Montana Territory to intercept and stop the
Nez Perce tribal band led by
Chief Joseph (1840–1904), after the
Nez Perce War, heading north to cross the border into
British Canada. For the rest of his career, General Miles would quarrel with General
Oliver O. Howard (1830–1909), who also led the pursuing expedition over taking credit for Chief Joseph's capture. Later while on the
Yellowstone River, he developed expertise with the use of the
heliograph for sending long-distance communications signals using sunlight and mirrors, establishing a line of stations with heliographs connecting far-flung military posts of
Fort Keogh and
Fort Custer, in the Montana Territory in
1878. The heliographs were supplied by Brig. Gen.
Albert J. Myer (1828–1880), of the
U.S. Army's
Signal Corps. In December
1880, Miles was promoted to brigadier general in the Regular Army. He was then assigned to command the military
Department of the Columbia (1881–1885) in
Oregon and the
Washington Territory, and subsequently the
Department of Missouri (1885–1886). In 1886, Miles replaced General
George R. Crook (1828–1890), as commander of forces fighting against
Geronimo (1829–1909), a
Chiricahua Apache renegade chief / guerrilla-fighter leader, in the military's
Department of Arizona in the old
Arizona Territory in the
Southwest. General Crook had relied heavily on
Apache scouts in his efforts to capture Geronimo. Instead, Miles relied instead on white regular cavalry troops, who eventually traveled without success as they tracked Geronimo through the tortuous
Sierra Madre Mountains of neighboring northern
Mexico. Finally, young First Lieutenant
Charles B. Gatewood (1853–1896), who had studied Apache culture and ways, succeeded in meeting with and negotiating a surrender of the war chief at a subsequent meeting arranged and held with General Miles, under the terms of which Geronimo and his few remaining followers agreed to temporarily spend two years in exile on a
Florida reservation far to the east. Geronimo agreed on these terms, being unaware of the real plot behind the negotiations (that there was no real intent to let them go back to their native lands in Arizona and New Mexico). The exile included even the Chiricahuas Apache scouts who had worked for the army, in violation of Miles' original agreement with them. Miles denied Lt. Gatewood any credit for the negotiations (or recommended him for a Medal of Honor) and had him transferred far north to the
Dakota Territory. During this campaign, Miles' special signals unit used the heliograph extensively, proving its worth in the field. The special signals unit was under the command of Captain
W. A. Glassford. In
1888, Miles became the commander of the Army's
Military Division of the Pacific and the
Department of California, headquartered at
The Presidio in
San Francisco. Two years later in April
1890, Miles was promoted to major general in the Regular Army and became the commander of the
Military Division of the Missouri. The
Ghost Dance movement of the
Lakota Sioux people, which started in 1889, led to the
Pine Ridge Campaign of the so-called Ghost Dance War and General Miles being brought back into the field. During the campaign, he commanded U.S. Army troops stationed near the several federal
Indian reservations in the new state of
South Dakota and hoped that Lakota chief
Sitting Bull could be peacefully removed from the
Standing Rock Indian Reservation. However, on December 15, 1890, Chief Sitting Bull was killed by
Indian agency police attempting to arrest him, and 14 days later on December 29, American cavalry troops surrounded and
massacred hundreds of Lakota Sioux at
Wounded Knee. Miles was not directly involved in the tragic massacre, and was critical of the Army's commanding officer of the reconstituted / reorganized and ill-fated
7th U.S. Cavalry Regiment in the field, Colonel
James W. Forsyth (1833–1906). Just two days after the massacre, Miles wrote to his wife, describing it as "the most abominable criminal military blunder and a horrible massacre of women and children". After his retirement from the Army a decade later, he fought for compensation payments to the Lakota Sioux survivors of the massacre. Overall, however, he believed that the United States federal government should have authority over the native Indians, with the Lakota under military control. ==Spanish–American War and later life==