Launched As Frères Baume in 1830 in Geneva, by brothers Louis-Victor and Célestin Baume, the model later partnered with Paul Mercier in 1918, getting to be the Baume & Mercier we know right now. In the course of a particularly tough period of time for the manufacturer, Baume & Mercier https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/