In 1933 the German Army Weapons Department issued a requirement for a light armoured vehicle weighing about 5000kg (11,025 lb) that could be used for training purposes, and five companies subsequentlay built prototype vehicles. After trials the Army Weapons Department accepted the Krupp design for further development, the design company being responsible for the chassis and Daimler-Benz for the superstructure. To conceal the real use of the vehicle the Army Weapons Department called the vehicle the Landwirtschaftlicher Schlepper (industrial tractor). The first batch of 150 vehicles was ordered from Henschel, and production commenced in July 1934 under the designation PzKpfw I(MG) (SdKfz 101) Ausf A and powered by a Krupp M 305 petrol engine developing only 57 hp (42 kW). There were problems with the engine, however, and the nextbatch Ausf B had a more powerful engine which meant that the hull had to be longer and an additional roadwheel added on each side. This model was a little heavier, but its more powerful engine gave it a maximum road speed of 40 km/h (25 mph). This entered service in 1935 under the designation of the PzKpfw 1(MG) (SdKfz 101) Ausf B. Most of the vehicles were built by Henschel but Wegmann also became involved in the programme, peak production being achieved in 1935 when over 800 vehicles were completed.
The Panzerkampfwagen l was first used operationally in the Spanish Civil War, and at the start of the invasion of Poland in 1939 no less than 1,445 such vehicles were on strength. It had already been realized, however, that the vehicle was ill-suited for front-line use because of its lack of firepower and armour protection (7-13mm/0.280.51 in), and in the invasion of France in 1940 only 523 were used, although many more were still in Germany and Poland. By the end of 1941 the PzKpfw I had been phased out of front-line service, although the kleiner Panzerbefehlwagen I (SdKfz 265) command model remained in service longer.
Once the light tank was obsolete its chassis underwent conversion to other roles, and one of the first of these was the Munitions-Schlepper used to carry ammunition and other valuable cargoes. For the anti-tank role the chassis was fitted with captured Czech 47-mm anti-tank guns on top of the superstructure with limited traverse, These were used on both the Eastern and North African fronts, but soon became obsolete with the arrival of the more heavily armoured tanks on the battlefield. The largest conversion entailed the installation of a 15-cm (5.9-in) infantry gun in a new superstructure, but this really overloaded the chassis and less than 40 such conversions were made.
The turret was in the centre of the vehicle, offset to the right and armed with twin 7,92-mm (0.31-in) machineguns, for which a total of 1,525 rounds of ammunition were carried. The driver was seated to the left of the turret.
Specification PzKpfw I Ausf B Crew: 2 Weight: 6000 kg (13,230 lb) Dimensions: length 4.42 m (14 ft 6 in); width 2.06 m (6 ft 9 in); height 1.72 m (5 ft 8 in) Powerplant: one Maybach NL 38 TR six-cylinder petrol engine developing 100 hp (75 kW) Performance: maximum road speed 40 km/h (25 mph); maximum road range 140 km (87 miles); fording 0.58 m (1 ft 11 in); gradient 60 per cent; vertical obstacle 0.36 m (1 ft 2 in); trench 1.4 m (4 ft 7 in)