Started As Frères Baume in 1830 in Geneva, by brothers Louis-Victor and Célestin Baume, the model later partnered with Paul Mercier in 1918, turning into the Baume & Mercier we know today. During a very demanding time period to the manufacturer, Baume & Mercier joined the Richemont team in 1988. https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/