Until the middle of the 20th century, it was assumed by most Catholics that most (if not all) non-Catholics were destined for eternal hellfire. ... Catholics felt a duty to work for the conversion of non-Catholics ... Catholics were wary of becoming too culturally close to non-Catholics. “Mixed marriages” were verboten, and Catholics tended to live together in small neighborhoods (the Catholic “ghetto”) in order to protect the faith of their impressionable children.
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