Started As Frères Baume in 1830 in Geneva, by brothers Louis-Victor and Célestin Baume, the manufacturer afterwards partnered with Paul Mercier in 1918, getting the Baume & Mercier We all know right now. Through a very hard period of time with the model, Baume & Mercier joined the Richemont group https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/