The Germans were the first to recognize the need for mounting anti-tank guns on an armored vehicle chassis, the first of which was the Panzerjäger I. This came about as a result of merging the hull of the Panzer I (already deemed obsolete when the war began) with a Czech-designed 4.7cm PaK(t) that was widely available after the annexation of Czechoslovakia in 1938 and was capable of destroying most Allied tanks that the Wehrmacht encountered during the early blitzkrieg campaigns. Due to weight issues, a proper turret or superstructure could not be built on top of the hull, instead, the Panzerjäger I had a large box-like shield that surrounded the gun mounting from the front and sides. However, both the back and the roof were open and the sides did not extend behind the breech. Although the armor was thin, it did provide the crew with some degree of protection but there were some limitations to the gun's traverse and elevation/depression. Panzerjägers were first seen in action during the invasion of Belgium and France in 1940 and they also saw widespread service during the early campaigns in North Africa. They were phased out by 1943 by which time they were obsolete. Nevertheless, their value as the first of a long line of German anti-tank vehicles based on tank hulls cannot be understated.

The first Panzerjäger I was constructed in 1939 with the conversion being undertaken by Alkett in Berlin. Production versions were based on the Ausf B version of the Panzer I.