1968, the US military needed to develop a lightweight howitzer as a replacement for the World War 2 M114 type 155mm howitzer. Two prototypes of the M198 howitzer were delivered to the army in 1972. After passing additional tests, the M198 howitzer was put into production in 1978. In April 1979, the first unit equipped with the M198 howitzer was officially formed.
After the M198 was put into production, more than 1,600 guns were produced. The last artillery piece rolled off the Iwashima Armory in 1992.