There have always been considerable differences between orthodox and liberal interpretations of Calvinism, such as those between Arminianism and Gomarism in the 17th century and those between the Dutch Reformed Church ("Nederlands Hervormde Kerk") and the Reformed Churches in the Netherlands ("Gereformeerde Kerken in Nederland") in the late 19th century, which even led to a denominational difference between "hervormd" and "gereformeerd", though linguistically both mean "reformed". Catholics, who dominated the southern provinces, were not allowed to practice their religion openly. They were emancipated during the late 19th and early 20th century through pillarization, by forming their own social communities. In 1947, 44.3% belonged to Protestant denominations, 38.7% belonged to the Roman Catholic Church, and 17.1% were unaffiliated. In 1940–45, 75-80% of Dutch Jews were murdered in The Holocaust by the Nazis.