The factory belonged to Etablissements Decauville ainé, a French manufacturer focussing on the production and sales of narrow gauge railway material.
It was located on a piece of land that Decauville had acquired in 1914 in the Seine-Saint-Denis department of the Île-de-France region in the north-eastern suburbs of Paris.
It focussed on tippers, i.e. V skip railway wagons and roadworthy dump trucks.
[2][3] The factory was renamed to Société Industrielle d'Aulnay in 1946, enabling the company to win a major contract.
At the factory Aulnay the last Decauville steam locomotives were built for the lignite mines of Yugoslavia.