During the war the Bay Area became the largest shipbuilding site in the world. New shipyards and expansions of existing ones constructed some fourteen hundred ships, averaging more than one a day. This rapid expansion of shipbuilding produced a huge demand for workers. Some new workers were local, including many women. Others were recruited across the country, including significant numbers from the South, both white and Black. One consequence was the expansion or development of Black communities in San Francisco, Oakland, Richmond, and Marin County.

Most shipyards had contracts with the International Brotherhood of Boilermakers, AFL, which limited membership to whites. The 1937 Boilermakers’ national convention had created a special status for locals considered subject to “subversive forces,” that is, the CP: the national officers took direct control of such locals. Local 513, for Kaiser Shipyard workers at Richmond, was controlled that way throughout the war, with no elections or meetings. Workers at Marinship, in Marin County just north of the Golden Gate Bridge, were represented by Boilermakers Local 6, a long-established local in San Francisco. Faced with many Black workers in the Bay Area shipyards, the Boilermakers required them to pay dues to an auxiliary but denied them participation in elections or meetings.27 CP members on opposite sides of the bay took different approaches to fight this racial discrimination.