Around 1850, Julien Belleville began making boilers for marine steam engines. Louis Delaunay became a partner in the company in 1867 and married Belleville's daughter. He would became sole owner and changed his and the company's name to Delaunay-Belleville.
Over the years, the company continued to grow, becoming an industrial manufacturer of boilers for locomotives and ships, as well as a supplier for battleships in the French navy. In 1903, Louis Delaunay-Belleville recruited Marius Barbarou from Benz, and S.A. des Automobiles Delaunay-Belleville was registered. Barbarou would become responsible for design and engineering, and one of his first creations was the round hood and radiator, which became a signature styling element of the marque.
At the Paris Saloon in 1904, Delaunay-Belleville presented their first automobile. It was a high quality vehicle powered by an advanced four-cylinder engine. As time progressed, the company gained a reputation for building silent, fast, and power automobiles. The cars they built were expensive, technically advanced, and built of superior quality. Their vehicles used some of the earliest pressure-lubricated camshafts and water-cooled brakes.
Tsar Nicholas II purchased a 40 HP Delaunay-Belleville in 1906. King George I of Greece and King Alphonso XIII of Spain also owned Delaunays.
In 1906, Delaunay-Belleville introduced the first six-cylinder chassis in France. The 70 hp vehicle was known as the Type SMT, or Sa Majesté le Tsar, as Nicholas II bought one of the early cars and a second in 1909.
In 1910, a silent starter that could be operated from the driver's seat was made standard. It was known as the Barbey starter, and was introduced three years before Charles F. Kettering developed the electric self-starter for Cadillac.