In 1849, Black miners discovered gold at Negro Bar as a battle raged at the California Constitutional Convention over whether California would enter the Union as a free or slave state. After much debate, California entered as a free state with the Compromise of 1850, but slavery persisted in the early years of statehood through the state's fugitive slave law passed in 1852. After the gold discovery, additional Black communities were established in upriver towns including Mormon Island, Negro Hill, Massachusetts Flat, and Coloma. Despite California's racially charged climate, by 1852 approximately 2,000 free Black people had made the state their home. In June 1854, Darius King opened an Express Office and bookstore at Mormon Island, providing a daily courier service between Sacramento, historic Negro Bar, and Mormon Island. Several other Black individuals opened additional businesses and built homes at nearby Negro Hill and Massachusetts Flat. In 1870, the local Folsom newspaper noted that three well-known Black residents, William Boswell, Harry Gibson, and Milton Rose, participated in the city's July 4th celebrations to commemorate the ratification of the 15th Amendment to the Constitution.