German luxury carmaker BMW will throw a lavish 100th birthday party on Monday, looking back at its often troubled history and forward as it seeks to adapt to the age of "personal mobility."In its home city of Munich the iconic headquarters, a complex dubbed the "BMW four-cylinder," towers as a source of pride while its vast plant, offices and museum are the southern city`s main private employer, with a total of 41,000 staff.Since its World War I beginnings, the company has grown into a multinational giant with plants in 14 countries, more than 116,000 employees and 80 billion euros ($88 billion) in annual sales.BMW today makes cars and motorcycles and its brands also include Rolls-Royce and Mini.Leading its rival Daimler-Benz in units sold, and with giant VW damaged by the emissions scandal, BMW remains in pole position at the high end of the auto industry and is seen as a symbol of German engineering prowess."It`s a great product, it`s a joy to make it," says Stefan Eichborn, wearing a blue overall and speaking in a Bavarian accent, as he supervises huge machines that press steel sheets into car body parts.- War-time past - The auto giant started life in far more troubled times – on March 7, 1916, making aircraft engines as Germany`s "Bavarian Aircraft Factory."After WWI, when defeated Germany was forbidden from manufacturing aircraft, it renamed itself Bayerische Motoren Werke ("Bavarian Engine Factory") in 1922.BMW adopted a propeller-shaped logo as a salute to its aerospace origins, in Bavaria`s traditional blue-and-white colors."The product for which BMW is best known nowadays was actually the last product to be taken into its portfolio," says Manfred Grunert, the company`s in-house historian.After producing its first motorcycle in 1923, BMW began making cars in 1928. During the 1930s it started on its own designs, such as the 326 limousine and the 328 roadster. As the Nazis came to power, BMW again became involved in armament efforts, once more building aircraft engines. From 1939 it used forced labour from concentration camps – one of BMW`s darkest chapters, which it only began to open up about in the 1980s.At the end of World War II, with Germany in ruins, the company survived by making household utensils. It resumed motorcycle production in 1948 and car production in 1952, but its success initially remained limited. "During the 1950s, BMW had serious financial problems," historian Grunert told AFP. "BMW did not participate in Germany`s post-war economic miracle."