Started As Frères Baume in 1830 in Geneva, by brothers Louis-Victor and Célestin Baume, the model afterwards partnered with Paul Mercier in 1918, turning into the Baume & Mercier we know nowadays. In the course of a particularly hard time period for that manufacturer, Baume & Mercier joined the Richemont https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/