The proud history of the Bushmasters dates back to 1865 when the 1st Arizona Volunteers organized to provide security in our nation’s southwest territory.  Follow-on service included the Spanish American War, Mexican border service, and World War I in France.

As a result of the declaration of a National Emergency in 1940, the 158th Infantry mobilized again – training in Oklahoma and Texas.  Then in 1942, following the December 7th, 1941 attack on Pearl Harbor, the 158th Infantry Regiment disembarked to the Panama Canal Zone. 

In Panama the 158th trained in jungle warfare.  Gaining fame for their newly acquired fighting skills, the Regiment took the name “Bushmasters” after the deadly bushmaster snake (indigenous to the region).  The name "Bushmasters" became well-known throughout the national press and General MacArthur personally requested the 158^th Infantry to serve in the Southwest Pacific Theater.

In January 1943 the Bushmasters staged in Australia.  From “Down Under” the 158^th Infantry advanced on and fought through Goodenought Island, Arawe, Wakde-Sarmi in Dutch New Guinea, and Neomfoor engaging and defeating Japanese units of division strength. 

In 1944, the Bushmasters landed in the Philippines and received a presidential citation for their success destroying or capturing 100 Japanese artillery pieces and enabling a successful invasion of the allies -- General MacArthur "had returned."

In 1945, the 158th Infantry pressed further in the Philippines, invading southern Luzon by means of a daring naval landing craft assault hitting the Legaspi Port.

As a result of the Bushmasters’ continued success, the 158th Infantry was selected to spearhead the final invasion of Japan. The Bushmasters were under orders to proceed two days ahead of America's crushing D-Day, to silence Japanese air warning stations south of Kyushu.  Timely capitulation of Japan saved the Bushmasters from what many believed would have been a certain suicide mission. 

In October 1945, the 158th Infantry landed in Yokohama, Japan.  The great odyssey was over.  FROM ARIZONA TO JAPAN - IN FIVE YEARS!  Members were then shipped home and the 158th was deactivated at Utsunomiya, Japan in January 1946.

In 1967, the unit converted and was Re-designated as the1583rd Military Police Battalion, 258th Military Police Brigade; then Re-designated again in 1969 as the 157th Military Police Battalion.