orld War 1 breaks out in 1914. André Citroën joins an artillery regiment and is sent to the front, where he notes that a lack of munitions is forcing the French army to save shells. Having visited the Henry Ford plant in the USA in 1912, André Citroën is familiar with the principles of work organisation. He believes that it would be possible to produce 10,000 shells daily in the first instance.

In 1915, while he ie on leave, he goes to see the French authorities and convinces them to set up a shell factory. In 1917, the Javel plant comes into operation. Built in just four months, specifically to make munitions, the plant regularly produces 50,000 parts daily - and sometimes more!

As the war draws to an end, André Citroën turns his attention to converting his munitions plant into a car plant. Like Henry Ford, he decides to make a single model with popular appeal. Before the war, car buyers bought a chassis without bodywork, mounted on wheels without tyres. André Citroën starts a revolution when he presents the Type A 10CV. Manufactured using volume production techniques, the Type A is delivered with a fully fitted body, equipped with four stamped metal wheels with tyres, a spare wheel, two headlamps and an electric self-starter.

This new form of production is a great success and the other French carmakers are forced to follow suit.

The Type A is the first in a long line of new models, each one sporting new features and innovations. The 5CV, presented at the 1921 Paris Show and more commonly known as the Trefle, is the first popular car built on a volume production basis.