Karl-Borromaeus Union, a Roman Catholic association in Rhenish Prussia, formed for the purpose of effecting in Roman Catholic society the same results for which the Gustavus Adolphus Society of the Protestant Church was founded. Perhaps, in a measure, it was intended to oppose any inroads of the Protestant association among the Roman Catholics. It originated in 1844, and makes it its special object to circulate at large the literary productions of Roman Catholics. The society publishes a monthly journal, and occasionally works of a religious character written in popular form. See Katholische Real-Encyklopadie, 11:835.