The 4CV was conceived and designed covertly by Renault engineers during the World War II German occupation of France. Development began between 1941 and 1944, while the manufacturer was under orders to produce only commercial and military vehicles. A design team led by Fernand Picard and Charles-Edmond Serre envisioned a small, economical car suitable for the post-war period. In May 1941, Louis Renault approved the project, then accorded the code "106E", despite German restrictions on new passenger car models. Development was defined as a low-priority spin-off from a project to develop a new engine for a post-war return of the Juvaquatre.
In November 1945, the French government invited Ferdinand Porsche to France to explore relocating the Volkswagen project. On December 15, 1945, Porsche was invited to advise Renault concerning the 4CV. Pierre Lefaucheux, the new head of Renault, was angered by the suggestion that the 4CV was inspired by the Volkswagen. Despite Lefaucheux’s objections, nine meetings with Porsche took place. Porsche cautiously predicted the car would be ready for large-scale production in a year. Shortly after the meetings, Porsche was arrested on war crimes allegations and spent twenty months in a Dijon jail.
The first prototype 4CV, featuring two doors, was completed in 1942, with two more produced in the following three years. Early in 1945, Lefaucheux tested the prototype at Louis Renault's Herqueville estate. By 1940, Louis Renault had directed his engineering team to "make him a car like the Germans'." The early 4CV featured a ‘dummy’ grille with six chrome strips, intended to distract from its similarity to the Volkswagen, while recalling designs from Detroit. Pierre Bézier, as director of production engineering in 1949, designed transfer lines for the 4CV’s mechanical parts, improving on automatic machine principles developed by General Motors.
The 4CV was presented to the public at the 1946 Paris Motor Show and went on sale a year later. Volume production commenced at the Billancourt plant a few weeks before the 1947 Paris Motor Show. Renault’s advertising highlighted the new manufacturing methodologies used in its assembly. The car was nicknamed "La motte de beurre" (the lump of butter) due to its shape and the sand-yellow paint used on early deliveries, surplus from Rommel’s Afrika Korps. It was also affectionately known as the "quatre pattes", "four paws".
Initially powered by a 760 cc engine, it was replaced in 1950 by a 747 cc version to stay beneath a 750 cc tax threshold. By mid-1949, 37,000 units had been sold, making it the most popular car in France. In 1950, 1,760 4CVs were sold in West Germany, accounting for 23% of imported cars. Power output increased to 21 hp, enabling a 0–90 km/h (0–56 mph) time of 38 seconds and a top speed barely under 100 km/h (62 mph).
The rear engine mounting resulted in highly geared, light steering – early cars required only 2¼ turns from lock-to-lock. Road tests warned of oversteer on wet roads, leading the manufacturer to increase the steering turns to 4½ on later models.
In early 1953, Renault launched a stripped-down version, the "Renault 4CV Service", with reduced tyre width, removal of the grille and chrome headlamp surrounds, and simplified seats. It retailed for less than 400,000 Francs. However, the "4CV Service" was discontinued after less than a year, potentially due to competition from the Citroën 2CV, which was cheaper despite its smaller 375 cc engine.
The Dauphine, launched in 1956, was the 4CV’s direct replacement, but the 4CV remained in production until 1961. It was ultimately replaced by the Renault 4, which used the same engine and sold for a similar price.
While most 4CVs were assembled at Renault’s Île Seguin plant, they were also assembled in Australia, Belgium, England, Ireland, Japan, Spain, and South Africa. In December 1949, assembly began at Renault’s Acton factory in West London. In Japan, Hino Motors assembled the car under license, rebadging it as the Hino Renault 4CV, and later the Hino Contessa. In Australia, the car was marketed as the Renault 760 and later the Renault 750.
A variant of the 4CV was the Renault Beach Wagon, also known as the Renault Jolly. Fifty were built by Ghia in 1961 using consecutively serial numbered 4CVs, with approximately a dozen estimated to exist today.
In 1996, Renault presented the Renault Fiftie concept car to celebrate the 4CV’s 50th anniversary. It was a two-door, mid-engine design with styling similar to the 4CV.