Little Willie was designed from July 1915 by the Landships Committee to meet Great Britain's requirement in World War I for a war engine able to cross a five foot trench. After several other projects with single and triple tracks had failed, on 22 July William Ashbee Tritton, director of the agricultural machinery company William Foster & Company of Lincoln, was given the contract to develop a "Tritton Machine" with two tracks, after a concept proposed by his chief designer William Rigby. It had to make use of lengthened tracks and suspension elements (seven road wheels instead of four) provided by the Bullock Creeping Grip Tractor Company in Chicago. When the tracks arrived it transpired they were very crude.
On 11 August actual construction began; on 16 August Tritton decided to fit a wheeled tail to assist in steering. On 9 September the Number 1 Lincoln Machine, as the prototype was then known, made its first test run in the yard of the Wellington Foundry. It soon became clear that the tracks were so flat that ground resistance during a turn was excessive. To solve this the suspension was changed so that the bottom profile was made more curved. Then the next problem showed up: when crossing a trench the track sagged and then wouldn't fit the wheels again and jammed. Tritton and Lieutenant Walter Gordon Wilson tried out all sorts of alternative track design including Balata belting and flat wire ropes. Tritton, on 22 September, at last devised a system using cast flat steel plates riveted to links and incorporated guides to engage on the inside of the track frame. This system was unsprung as the tracks were held firmly in place, able to move in only one plane. The track frames as a whole however were connected to the main body by large spindles allowing for a modicum of movement in relation to the hull. This was a successful design and was used on all First World War British tanks up to the Mark VIII though it limited speed.
Je to trochu dlouhé, ale asi tam důvod tohoto názvu najdeš. A ne-li, všimni si, že William Ashbee Tritton, ředitel zemědělské strojírenské společnost William Foster & Company v Lincolnu, v Anglii, měl stejné křestní jméno jako bylo křestní jméno majitele společnosti, tak by bylo jistě i divné, kdyby se ten tank jmenoval jinak než Vilík.