Belle Cora, also known as Arabella Ryan, was a madam of the Barbary Coast of San Francisco during the mid-nineteenth century. She rose to public attention in 1855 when her lover, Charles Cora, killed U.S. Marshal William H. Richardson after they had a conflict at the theater. She died in 1862.

The Barbary Coast was a red-light district during the second half of the 19th and early 20th centuries in San Francisco that featured dance halls, concert saloons, bars, jazz clubs, variety shows, and brothels. Its nine block area was centered on a three block stretch of Pacific Street, now Pacific Avenue, between Montgomery and Stockton Streets. Pacific Street was the first street to cut through the hills of San Francisco, starting near Portsmouth Square and continuing east to the first shipping docks at Buena Vista Cove.