The sport of roller derby has a somewhat convoluted history, but it's enough to know that in the 1960s there were two rival roller derby franchises. Each had a series of teams that traveled around the country playing each other. The first, owned by the Seltzer family, had a monopoly on the name "roller derby". The second referred to the sport as "Roller Games" and did business internationally under various names such as the National Roller League, Canadian National Roller League, and Japanese National Roller League. Due to dwindling popularity by the mid-1970s both franchises were effectively out of business although they continued to reincarnate themselves in periodic (often brief) attempts to revitalize the sport.
Roller Games
