In July 1871, U.S. Army General
George Stoneman (1822-1892), hired Sieber as Chief of Scouts and he served for much of the
Apache Wars. He participated in General
George Crook's Tonto (Apache) campaign (1871–1873). When the
Camp Verde, Arizona Territory Indian reservation was closed, Sieber was told to move Yavapais and Tonto
Apaches to the
San Carlos Reservation in the middle of winter. He remained employed there and participated in several engagements with Apache groups that had abandoned and left the reservation. On October 24,
1874, the
Arizona Miner newspaper (in
Prescott of northern
Arizona Territory), reported, "Al Zieber, Sergeant Stauffer and a mixed command of white and red soldiers are in the hills of Verde looking for some erring
Apaches, whom they will be apt to find." Three days later, Sieber and Sgt. Rudolph Stauffer found the Apaches that had escaped the reservation at
Cave Creek and fought them.
Josephine ("Sadie") Marcus Earp (1861-1944, future wife of famed lawman
Wyatt Earp (1848-1929), wrote that when she arrived in the Arizona Territory, coming to
Tombstone, she learned that "some renegade Yuma-Apaches had escaped from the reservation to which they had been consigned and had returned to their old haunts on the war-path" and that Sieber was tracking the escaped Apache. She said Sieber and his scouts led her stagecoach and its passengers to a nearby adobe ranch house where they remained until the Indians were captured. In February, April, and May 1877, Sieber acted as a guide for
Pima County Marshal Wiley Standefer, who was pursuing outlaws in the region. In
1883, General Crook with a unit of
American cavalry went south into the
Sierra Madre Mountains of northern
Mexico pursuing Apache renegade chief
Geronimo (1829-1909), with a band of rebelling Indians in the
Geronimo Campaign. Sieber was Crook's lead civilian scout and mentor to
Tom Horn, whom he taught to speak
German, as well as fighting together during the battles at
Cibecue Creek (August 1881), and
Big Dry Wash (July 1882). Sieber was in the field but not present when the Apache leader and renegade
Geronimo surrendered to young Lt.
Charles B. Gatewood (1853-1896), and commanding General
Nelson Miles (1839-1925), in September
1886, finally ending the Indian Wars in the old Southwest. Sieber stayed on at San Carlos as Chief of Scouts for the Army for another 13 years. == Wounds ==