Now free to own land in his own name, Larkin turned his attention to his new opportunities. In partnership with Robert Semple, he established the city at the Carquinez Straits that became Benicia, but Larkin’s business interests were in San Francisco and he sold out his share after a few years. As he took control of his own affairs, his relationship with Leidesdorff fell apart. By the time of the Gold Rush, Larkin had permanently settled in the city by the Bay and was there in time for the economic boom that followed. It was as a representative from San Francisco that he served at the 1849 Constitutional Convention, held in Monterey.