On December 24, 1890, The Oklahoma Territorial Governor approved an act by the Territorial Government for an establishment of military companies. However, this act did not fully fund the state militia. It wasn't until December 1894 that the Oklahoma Territorial Militia got its first Adjutant General. By the end of 1895, the Oklahoma Territorial Militia had become the Oklahoma National Guard composed of eight companies with a total of 353 citizen soldiers. The Guard was decimated when the United States went to war with Spain in 1898 as those citizen soldiers volunteered for military service.
After the war, Chandler resident Roy Hoffman held a meeting in town which reorganized the Oklahoma National Guard. The first annual encampment was held in Guthrie in 1899. As funding for the Guard was still inadequate, the encampments were only held in cities that would fund hosting them. In 1909, the Oklahoma National Guard built the State Camp and Maneuver Grounds and Rifle Range in Chandler, the first permanent structures for the Guard in Oklahoma. It consisted of a 1200-yard rifle range, a statistical house, a bath house, a warehouse to store the Guard's equipment, and a stairway up the hill to the warehouse. The Guard's 1909 encampment was held on those grounds and every year afterwards up to 1916.
The Oklahoma National Guard grew up in Chandler, primarily due to Roy Hoffman's stewardship. In 2010, Hoffman was inducted into the Oklahoma Military Hall of Fame and officially recognized as the Father of the Oklahoma National Guard. In 2024, Chandler was officially recognized as the Hometown of the Oklahoma National Guard. The stat house, stairway, and part of the rifle range still exist here in Chandler, evidence of the adolescent years of the Guard.
