from Wikipedia
Contemporary roller derby is an American-invented contact sport with roots in sports entertainment. The game is based on formation roller skating around an oval track by two teams. Points are scored as the designated scoring player (the “jammer”) of each team laps members of the opposing team, including its “blockers,” hence offense and defense typically occur simultaneously.
Roller derbies were originally straightforward amateur or professional (paid) endurance races on roller skates which were popular from the 1880s into the 1920s. A popular, multi-day touring exhibition of such races, created by Leo Seltzer, began in 1935 during the Great Depression, which simulated cross-country races by professional, two-person, male-female teams. Soon thereafter the teams were restructured, a point-scoring system was enacted, the endurance aspect was abandoned, and forms of contact were allowed, creating the basic format of contemporary derby.
In the 1950s skaters occasionally staged theatrical plays, but by the 1960s and into the 1970s the sport had evolved more into a form of sports entertainment in which the theatrical elements typically overshadowed the athletic and sporting aspects. The gratuitous showmanship largely ended with the sport’s grassroots mid-2000s revival and subsequent evolution. Contemporary derby is international and predominantly female with over 600 women’s leagues, in more than 20 countries as well as a growing number of male, co-ed, and junior leagues. (Furthermore, it is not exclusively a young woman’s game, inasmuch as many women over 40 also participate.) Leagues typically operate on an amateur circuit, and are based on a strong do it yourself ethic which features both athleticism combined with elements from punk and third-wave feminist aesthetics.
Contemporary roller derby is played by rulesets created by organizational bodies which include the Women’s Flat Track Derby Association (WFTDA), World Organization of Roller Derby (WORD) and Old School Derby Association (OSDA). The WFTDA ruleset is the most commonly used today.
