The California Avenue Congregational Church was first gathered in 1883 and the church building was constructed in 1887. The church federated with the Monroe Street Church of Christ to form the Monroe Street Federated Church in 1918. The church dissolved in 1933. This collection primarily contains administrative and membership related records and includes vital membership records, church meeting minutes, a newsletter, and directory.

An unknown congregationalist organization sent out surveys to many of the congregational churches across the contiguous 48 states to record levels of patriotism post-World War I. These surveys contain details of congregational church participation and support of the American war efforts, and what their post war transition looked like.