After World War 1, Germany was forbidden by the treaty of Versailles to possess or produce tanks. However, during the 1920s a variety of weapons, including AFVs, were developed in secret and, with the connivance of the Soviet Union, were tested at Kazan in Russia. After the rise of Hitler, rearmament was accelerated and plans were laid for the development of purpose-built battle tanks that eventually emerged as the Panzers III and IV. As an interim measure, a vehicle was required for the training of armoured forces and, in 1933, prototypes of a simple, cheap and easy to manufacture tank were invited from a number of firms. A design by Krupp, based on the Carden-Lloyd tankette, was selected and production began in 1934 under the code-name Landwirtschaftlicher Schlepper or 'agricultural tractor'. Later designated Panzerkampfwagen I it was 13ft long and weighed 5.4 tons, with a crew of two. Armament was two 7.92mm machine guns and 3,125 rounds of ammunition were carried. In 1935 a further stopgap machine, the Pzkpfw II, was produced, weighing 10 tons and armed with a 20mm Kwk 30 gun with a co-axial 7.92mm machine gun. Blooded in the Spanish Civil War, these erstwhile training machines were numerically the most important tanks during the early campaigns of World War 2 and their contribution to the success of Blitzkrieg warfare was considerable. As the first German tanks to be developed subsequent to the Treaty of Versailles, there can be no more appropriate marque of vehicle to start Ian Allan Publishing's new series devoted to classic armoured vehicles. Drawing upon archive photographs, line drawings and specially prepared colour artwork, the book describes in detail the development of the early Panzer models. Alongside the illustrations, the author's erudite text puts the designs into their historical context, providing the reader with a comprehensive study of these important, but often overlooked, German models. Designed with the war-gamer and military historian in mind, Ian Allan Publishing's new 'Tanks & Armour' series represents an excellent pictorial reference to many of the most important tank designs of the 20th century.