Chevrolet
Swiss Louis Chevrolet had a background in automobile factories in France before emigrating to North America, ending up becoming well known as a race car driver in the USA, which led to his driving the Buick race cars for owner William Durants Buick team, while at the same time had shown himself as a capable designer with his own workshop where he designed and built prototype engines, and a small race car called the Cornelian. By late 1911, capitalising on his own Chevrolet name, the Chevrolet company was started with one of his brothers and various well known auto makers including William Crapo Durant, to help fund the project. But there was a falling out by 1915 (the same year Louis became a US Citizen) over the direction of teh company. Durant wanted a mass produced car to compete with Fords Model T and Louis wanted the marque to be a higher performance more expensive car. This led to Louis Chevrolet selling his interest in the company to Durant and left to persue other projects (such as Monroe, Frontenac, speed parts and aircraft engines). The Chevrolet brand was so successful that the proceeds generated allowed Durant to purchase and regain the controlling interest in General Motors, after which the Chevrolet brand was merged into General Motors, where the Chevrolet marque was placed to compete with Ford.
I would recommend anyone interested in Louis Chevrolet and his brothers to check out the totally absorbing website researched and compiled by my friend William Dunbar on chevroletbrothers.com