Infantry in WWI often faced well protected lines of trenches, defended by machine gun nests with interlocking fields of fire.

The combatants experimented with mortars, rifle grenades, and mountain guns in search of an answer but these positions could only be defeated by direct-fire artillery support.

Small caliber mountain guns and mortars such as the Skoda 75 mm Model 15 and the German 7.58 cm Minenwerfer showed promise, but their size and weight combined with the roughness of the terrain weighed against their use.

The precision of the 3.7 cm Infanteriegeschütz M.15 compensated for the reduced caliber of the ammunition and the lightness of the piece allowing it to be transported during assaults, unlike the mountain guns used until then in the same role.

The gun fired Fixed QF 37×57 mm R ammunition, available in high-explosive, shrapnel and tracer which were carried in wooden crates of 15 projectiles, weighing 26.5 kg (58 lb 7 oz), a development which could be considered an early equivalent to today's grenade cartridges such as the 35×32mmSR and 40×53mmSR shells.