Emil Seidel (December 13, 1864 – June 24, 1947) was born in Ashland, Pennsylvania, USA. His family moved to Wisconsin when he was a child. As a young man he lived in Germany where he trained as a woodcarver and also became a socialist.

When he returned to the United States he joined the Socialist Party of America. Settling in Milwaukee, he and eight other socialists were elected as city aldermen in 1904.

In 1910, Seidel was elected mayor of Milwaukee, becoming the first socialist mayor of a major city in the United States. During his administration the first public works department was established, the first fire and police commission was organized, and a city park system came into being. Seidel cleaned the town up with strict regulation of bars and the closing of [Prostitution|brothels] and sporting parlors (modern-day casinos).

In the 1912 mayoral election, the Democratic and Republican parties joined forces to defeat Seidel, resulting in his lose to Gerhard Bading . Seidel then chose to run for Vice President of the United States on the Socialist ticket with Eugene V. Debs, and the pair won a respectable 897,011 votes in the 1912 presidential election. Siedel served two more terms as alderman, in 1916-20 and 1932-36, before his death.