The German Army came upon the Soviet 122 mm field guns and issued a requirement for a similar weapon.

However, once heavier Soviet tanks such as the IS-2 started to appear, the design requirements were altered to include an anti-armour role.

Rheinmetall had developed a variant of the 128 mm Flak gun, whilst Krupp opted to design a new weapon from the ground up.

The gun was fed with two-piece ammunition, the projectile and cartridge making up separate pieces.

The light and medium charges were normally used when the gun was fulfilling the role of an artillery piece, where they would launch the c. 28 kg projectiles to a muzzle velocity of 845 m/s and 880 m/s respectively.

[1] The 12.8 cm Pak 44 ended up becoming the standard main armament for the Jagdtiger heavy tank destroyer and a tank gun variant was the planned main armament for many future super-heavy tank designs in development during the last months of World War II, including the fully turreted Panzerkampfwagen Maus and E-100, as the 12,8 cm KwK 44 L/55 main gun.