San Francisco was a relatively new town when it was hit by its first organized street gang. The Sydney Ducks arrived at the height of the Gold Rush, mostly Irish who’d spent time in Australia—either as laborers or convicted criminals. They staked their claim in the rough district later known as the Barbary Coast.
In California, they specialized in robbery, assault, extortion and arson. They set an 1849 fire that devastated much of the downtown area. The vigilante movement of 1851 forced many of the Ducks to flee the area.