 Ottomans practiced "devşirme", a sort of "blood tax" or "child collection", young Christian boys from the Balkans and Anatolia were taken from their homes and families, brought up as Muslims, and enlisted into the most famous branch of the "kapıkulu", the Janissaries, a special soldier class of the Ottoman army that became a decisive faction in the Ottoman invasions of Europe.During the various 18th and 19th century persecution campaigns against Christians as well as during the culminating Assyrian, Armenian and Greek genocides of World War I, many indigenous Armenian, Assyrian and Greek Christian women and children were carried off as slaves by the Ottoman Turks and their Kurdish allies.Henry Morgenthau, Sr., U.S.