2018 San Francisco mayoral special election
Ed Lee, who was appointed Mayor of San Francisco in 2011 following Gavin Newsom's election as Lieutenant Governor of California, elected to a full term in 2011, and reelected in 2015, died of cardiac arrest on December 12, 2017. London Breed, the President of the San Francisco Board of Supervisors, became the city's acting mayor.
Moscone–Milk assassinations
The Moscone–Milk assassinations were the killings of San Francisco Mayor George Moscone and San Francisco Supervisor Harvey Milk, who were shot and killed in San Francisco City Hall by former Supervisor Dan White on November 27, 1978. White was angry that Moscone had refused to reappoint him to his seat on the Board of Supervisors, from which he had just resigned, and that Milk had lobbied heavily against his reappointment. These events helped bring national notice to then-Board President Dianne Feinstein, who became the first female mayor of San Francisco and eventually U.S. Senator for California.