William Stephens was born in Eaton, Ohio, on 26th December, 1859. After graduating from Eaton High School he studied law. Later he became involved in the construction of railroads in Ohio, Indiana, Iowa and Louisiana.
In 1887 Stephens moved to California and established a wholesale and retail grocery business. He was president of the Los Angeles Chamber of Commerce before becoming mayor of Los Angeles in 1909.
A member of the Republican Party, Stephens was elected to Congress in 1910 and served from March, 1911 to July, 1916. The following year he was elected as Governor of California. During his period of office the state suffered from serious industrial disputes and acts of terrorism, including the bombing of the Governor's Mansion in 1917.
After leaving office he worked as a lawyer in Los Angeles. William Stephens died on 24th April, 1944.