Diatto Clément-Bayard Series History

In 1905, grandsons of the company founder, Vittorio and Pietro Diatto, formed 'Società Diatto-A. Clément' in partnership with French industrialist Adolphe Clément-Bayard, producing automobiles under licence from Clément-Bayard. The cars used four- and six-cylinder engines of 10/12 hp, 12/16 hp, and up to a 24 hp six; the factory employed around 500 workers — comparable in scale to Fiat at the time.

Competition appearances began almost immediately: in 1906 Diatto won the Herkomer Competition in Germany (1,800 km from Frankfurt to Innsbruck), the Lugano–San Gottardo mountain speed trial in Switzerland, and the Italian Gold Cup over 4,000 km. When Clément-Bayard withdrew from the partnership in 1909, the Diatto brothers bought out his interest and rebranded as Autocostruzioni Diatto, shifting to fully independent design.