Beginning in the 1880s, the Church in America was rocked by a series of debates that historians later came to call collectively the Americanist controversy. In general, disagreements revolved around how an increasingly immigrant church would relate to its host country: Would American Catholics retain strong ties to Europe and maintain their native languages, or would they attempt to assimilate as quickly as possible?
A number of bishops became known as the main combatants on one side or the other. For the "Americanists," Abp. John Ireland of Minneapolis, Bp. John Lancaster Spalding of Peoria, and Cardinal James Gibbons of Baltimore, were important figures. On the other side were Bishop Bernard McQuaid of Rochester and Abp. Michael Corrigan of New York.
Pope Leo XIII made an apparent intervention in the debates when he issued Testem Benevolentiae in 1899 and condemned "Americanism." Most American Catholics, however—including so-called "Americanists"—disavowed the unacceptable propositions identified by Leo, and in any case, the background of the letter made it appear to be directed more at European than at American controversies.