The rebellious Netherlands that had united in the Union of Utrecht ( 1579 ) declared their independence from Spain in 1581 , during the Eighty Years ' War ; Spain finally accepted this in 1648 . The Dutch revolt was partially religiously motivated : during the Reformation many of the Dutch had adopted Lutheran , Anabaptist , Calvinist or Mennonite forms of Protestantism . These religious movements were suppressed by the Spanish , who supported the Counter Reformation . After independence the Netherlands adopted Calvinism as a quasi state religion ( although never formally ) , but practiced a degree of religious tolerance towards non-Calvinists . It became considerably safe for Jewish and Protestant refugees from Flanders , France ( Huguenots ) , Germany and England ( Pilgrims for instance ) . There have always been considerable differences between orthodox and liberal interpretations of Calvinism : between Arminianism and Gomarism in the 17th century ; and 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 meaning " 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
The Holocaust
The Holocaust
Religion in the Netherlands