USA: By 1850, Roman Catholics as a percentage of the US population had significantly increased from its tiny minority position at the time of the Revolution and the original Thirteen Colonies to an increasingly significant portion of the population. (The original colonists were overwhelmingly Protestant, as more often than not; they had come to America to flee Catholic persecution in Europe).
As regards the Jews, in particular, the Roman Catholic priests regrettably often brought with them fundamentalist “theological baggage” from Europe, hazardous to the health of the Jewish life in America. For the Jews, by the mid–1800s, with Catholic immigration ascendant, the “ecumenical honeymoon” from the time of the Revolutionary War, would be long gone. Toxicity would seep out of Catholic churches and Catholic schoolyards, and into society at large.