As the frontier pushed westward, touring companies quickly followed. California scarcely qualified as frontier by the 1880s, but many towns between Chicago and San Francisco still had the volatile populations that craved lively entertainment. Performances in frontier towns were usually presented in a second- or third-floor hall above commercial space; often actors and spectators used the same exterior staircase. Audiences in such venues tended to be almost entirely men. Legitimate plays were presented with musical or specialty numbers between the acts. Not until a town built its first opera house could it offer a better class of attractions, but by then it could no longer be called a frontier town.
The Historical Dictionary of the American Theater. James Fisher.