Columbia subject headings:
Harvard subject headings:
Catholic Church--Europe--History--20th century.
Europe--Church history--20th century.
Islam--Mediterranean Region--History--20th century.
Judaism--20th century
Mediterranean Region--Religion.
Protestant churches--United States--History--20th century.
Radicalism--Religious aspects--History--20th century.
Religion and international relations.
Religion and politics
Religions--History--20th century.
United States--Church history--20th century.
Princeton subject headings:
Religion--History--20th century.
Religion--Social aspects.
Religions--History--20th century.
Social change.