Started As Frères Baume in 1830 in Geneva, by brothers Louis-Victor and Célestin Baume, the brand later on partnered with Paul Mercier in 1918, getting the Baume & Mercier we know these days. During a very demanding interval for that manufacturer, Baume & Mercier joined the Richemont group in 1988. https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/