In 1963 the United States and Germany made an agreement to create a new main battle tank that both countries would produce, and that would be ready for production by 1970: this was the MBT-70 program.

With the outbreak of the Korean War in 1950, the U.S. Army found itself without a suitable tank to counter the huge number of vehicles in the Soviet inventory. The Army launched a two-pronged program to begin correcting this major deficiency: the first prong was the development of the M47, which was a stop-gap solution; the second was to develop the M47's successor, which became the M48 Patton tank.

The M47 was developed in response to the U.S. Army's lack of a capable tank to fight in the Korean War, which broke out in June 1950. The tank was actually a hybrid of sorts, and merged the T42 turret with the proven M46 chassis.

Bofors of Sweden was awarded a contract in 1958 to develop a turretless tank for the Swedish Army. Two prototypes were ready in 1961, and series production of the Stridsvagn 103 (a.k.a. the "S-Tank") began in 1967. A total of 330 StrV 103's were built in three versions (A, B, and C), with production ending in 1971.