Ben-Gurion was living in Jerusalem at the start of the First World War, where he and Ben Zvi recruited forty Jews into a Jewish militia to assist the Ottoman army.
On his arrival, he and Ben Zvi went on a tour of 35 cities in an attempt to raise a Hechalutz "pioneer army" of 10,000 men to fight on Turkey's side.
[3] After the Balfour Declaration of November 1917, the situation changed dramatically and Ben-Gurion, with the interest of Zionism in mind, switched sides and joined the newly formed Jewish Legion of the British Army, leaving to fight the Turks in Palestine.
At its peak, between 1930 and 1935, HeHalutz operated in 25 countries throughout Europe, North Africa, the Middle East, and Northern South America.
[5] In 1933, after Jews were expelled from the workforce in Nazi Germany, HeHalutz farms became the primary framework for vocational training and preparation for emigration.