Léon Breitling was born in 1860. After the end of the apprenticeship he went into businnes for himself and 1884 at the young age of 24 years founded the small manufacturing "G Leon Breitling" in Saint-Imier (Bernese Jura) . There he produced complicated watches, chronographs and chronometric instruments. 1892, he moved with his company to La Chaux-de-Fonds to larger production facilities in a building shared with Couleru-Meuri. The company now called itself “Leon G. Breitling Montbrillant SA Watch Factory” and had 60 employees.