Detroit Streetcar Workers Unionize, Riot, & Win| May 12

On this day in 1891, Detroit’s streetcar employees unionized. Starting in April, local transit workers picketed the Detroit Street Railway and Grand River Railway companies, leading to a violent 3-day riot. They sought a 10-hour workday instead of 12. After Mayor Hazen Pingree intervened, an agreement was reached on May 12, recognizing the new union.