The Minor was conceived in 1941. Although the Nuffield Organization was heavily involved in war work and a governmental ban existed on civilian car production, Morris Motors' vice chairman, Miles Thomas, wanted to prepare the ground for new products to be launched as soon as the war was over.  Vic Oak, the company's chief engineer, had already brought to Thomas' attention a promising junior engineer, Alec Issigonis, who had been employed at Morris since 1935 and specialised in suspension design,  but he had frequently impressed Oak with his advanced ideas about car design in general.

With virtually all resources required for the war effort, Thomas nonetheless approved the development of a new small family car that would replace the Morris Eight. Issigonis was ultimately responsible for the design, working with only two other draughtsmen. The project was named 'Mosquito' kept as secret as possible, both from the Ministry of Supply and from company founder William Morris (Lord Nuffield), who was still chairman of Morris Motors, and as widely expected, would not look favourably on Issigonis' radical ideas.

Issigonis' overall concept was to produce a practical, economical, and affordable car for the general public that would equal, or even surpass, the convenience and design quality of a more expensive car. In later years he summed up his approach to the Minor; that he wanted to design an economy car that "the average man would take pleasure in owning, rather than feeling of it as something he'd been sentenced to" and "people who drive small cars are the same size as those who drive large cars and they should not be expected to put up with claustrophobic interiors." Issigonis wanted the car to be as spacious as possible for its size, and comfortable to drive for inexperienced motorists. Just as he would with the Mini 10 years later, he designed the Mosquito with excellent roadholding and accurate, quick steering, not with any pretence of making a sports car, but to make it safe and easy to drive by everyone.

The car was launched in 1948 and remained in production until 1972. There were two and four door saloon variants, a convertible, a wood framed estate car, a van and a pickup. The design was continuously revised during its production life with the last major overhaul to the MkV occurring in 1962. It is rightly considered a design classic and was a big factor in getting post-war Britain mobile.