Columbia subject headings:
Dioceses--France--History--20th century.
Dioceses--Germany--History--20th century.
World War, 1914-1918--France--Religious aspects.
World War, 1914-1918--Germany--Religious aspects.
Harvard subject headings:
Catholic Church--History--20th century.
Europe--Church history--20th century
World War, 1914-1918--Religious aspects--Catholic Church
Princeton subject headings:
Catholic Church--History--20th century.
Europe--Church history--20th century.
World War, 1914-1918--Religious aspects--Catholic Church.