Ossa is a Spanish motorcycle manufacturing company which was founded in 1924, being initially focused on producing movie projectors for the Spanish market. It's interesting to note that Ossa followed the same trend market as many other motorcycle companies at the end of World War II when lots of manufacturers started building two stroke motorcycles. In comparison with the other companies, Ossa took advantage of the technology powered by DKW, (Manuals page) a German company which was already building two stroke engines.
However, Ossa managed to launch its first line of motorcycles in 1949 but it didn't record too high sales in the first years of availability. What's interesting is that the company recorded an impressive growth in sales during the 1960s when most of its motorcycles were exported to other markets, including the American one. In fact, the United States industry is one of the markets which quickly adopted the Ossa motorcycles and numerous bikes could be still seen in the US nowadays.
Although it built a lots of models of street bikes, the company has also been focused on racing motorcycles for several years. For instance, Ossa released special bikes for motocross and trials as well as special motorcycles for enduro competitions. The Spanish firm rolled out an important number of famous models, including the Copa 250, the Explorer, the Formula 3, the Mountaineer, the Pioneer, the Six Day Replica and the Turismo.
Although it all looked to go pretty well for the Spanish company, Ossa started experiencing financial problems in the '70s when the Japanese companies began distributing their motorcycles in multiple countries of the world. Thanks to the performance they provided and also thanks to their prices, these bikes were pretty attractive even for the consumers who were previously interested in Ossa's motorcycles so the Spanish manufacturer had to revamp the company.
In order to do so, it merged with Bultaco (Manuals PDF page) in 1979 but even if it looked like a way to save the company, it actually didn't do it so Ossa was forced to close its factories in 1982.