 Following his graduation, Augur served as aide-de-camp to Generals Hopping and Cushing during the Mexican–American War, and during the 1850s took an active part in the campaigns of the western frontier against the Yakima and Rogue River tribes of Washington and, in 1856, against the Oregon Indians.In Oregon, he was responsible for building Fort Hoskins in Kings Valley.Augur was promoted to the rank of Major in the 13th Infantry on May 14, 1861.