Established in 1871, Benz & Cie. was the most important of several companies founded by Karl Benz. The Benz patent motor wagon was ahead of its times; by 1886, Benz had the first four-stroke engine. Karl Benz is credited as the inventor of the first "true" automobile since Daimler's vehicle was a horse carriage adapted with an engine, whereas the 1886 Benz automobile had a chassis designed from scratch. Daimler Motoren Gesellschaft-(DMG) was founded by Gottlieb Daimler and his partner Wilhelm Maybach in 1890. Daimler died in 1900 and Maybach left DMG in 1907. By then, Benz & Cie. and DMG were rivals. In 1924, owing to economic necessity after World War I, they entered into an "Agreement of Mutual Interest" valid until the year 2000. This initial agreement still allowed each company to manufacture and sell their products under their original brand names. After the official merger in June 28, 1926, the firm became known as Daimler-Benz. The hyphenated brand name Mercedes-Benz was established after that merger. The brand name Daimler had been licensed for use on other automobiles in France and the United Kingdom, and was therefore not available to Daimler-Benz. Instead, the name of its seminal Mercedes model designed by Maybach over twenty years before was chosen for the DMG portion of the new brand. ("Mercedes" had been painted on a DMG vehicle used in races by a man in honor of his daughter, and became the formal name of a DMG model in 1902, see below.) Thus, Mercedes-Benz became the brand name applied to the models of one of the new firm. Because of its eponymous tie to Karl Benz and his early vehicles, Mercedes-Benz is also the name of the world's oldest continuously produced automobile line.