During the nineteenth and early twentieth centuries, Black athletes were barred from playing baseball in the major and minor leagues, as well as other teams of white players, with relatively few exceptions. Research on baseball’s color line has primarily focused on organized baseball (the major and minor leagues). The nine essays in this monograph are an introductory exploration of integrated baseball in California at various levels, from amateur to professional teams. The first six essays are biographies of seven Black ballplayers who played on predominantly white teams engaged in intercity competition for multiple years from 1886 to 1909. The seventh essay presents information about Black umpires in the state who officiated games involving one or two white teams. The eighth essay is the story of William Carroll and the Trilbys of Los Angeles, a prominent Black baseball club at the turn of the century. The final essay examines possible patterns associated with where and when the integrated teams played in California, supplemented by descriptions of the experiences of three Black soldiers of the 24th and 25th US Infantries who integrated teams west of the Rocky Mountains after their discharges from the army.