Haqanah

Haganah evolved from the League of Nations Mandate for Palestine which was administered by Great Britain. Article 4 of the League of Nations Mandate for Palestine recognized a public body for the purpose of advising and cooperating with the Administration of Palestine in such economic, social and other matters as may affect the establishment of the Jewish national home...and...to assis and take part in the develop-merit of the country."

Although the Haganah had no legal status and was not recognized by the British mandatory authority, it was tolerated by the British because its "aims were defensive." 

Concurrent with the 1936-39 Arab Revolt, Haganah Command tightened its control over its combatants and Special Night Squads were organized in conjunction with the British to retaliate against the Arabs. The Jewish squads were equipped an trained by the British under Captain Charles Orde Wingate. Initially, 2800 Jews were enrolled as constables by the British to com bat the Arab insurgents. This number eventually rose to 5000 at the peak of the violence. In 1936, Haganah strength was 10,000, including reserves.

Three separate organizations within Haganah appeared in the late 1930's: Mosad, Shai and Palmach. The Mosad was centered in Paris. Its primary concern was the immigration of Jews from Eastern Europe to Palestine via Mediterranean ports.

Shai was Haganah counter-intelligence. Although operating primarily against the British in Palestine, it also gathered intelligence on Arab opponents. By 1947, Shai had infiltrated every aspect of the Mandatory Administration with a force of over 2000 members.

Palmach was the striking arm of Haganah. Comprised of about 3000 men, women and youths, the Palmach were regular, salaried commandos. These left-wing Zionists were led by Moshe Sneh, who was succeeded in 1946 by Itzhak Sadeh. The Palmach led the British invasion in 1941 to flush the Vichy government out of Syria and Lebanon.