Hagana

ההגנה Haganah
Haganah symbol
Active	1921–1948
Country	Yishuv, Mandatory Palestine Israel
Type	Paramilitary (pre-independence) Unified armed forces (post-independence)
Role	Defense of Jewish settlements (pre-independence)
Size	Average: 21,000
Engagements	Palestinian Arab revolt World War II Palestine Civil War 1948 Arab-Israeli War (for two weeks)
Disbanded	May 28, 1948

Haganah (Hebrew: הַהֲגָנָה‎, lit. The Defence) was a Jewish paramilitary organization in the British Mandate of Palestine (1921–48), which became the core of the Israel Defense Forces (IDF).

The evolution of Jewish defense organisations in Palestine and later Israel went from small self-defense groups active during Ottoman rule, to ever larger and more sophisticated ones during the British Mandate, leading through the Haganah to the national army of Israel, the IDF. The evolution went step by step from Bar-Giora, to Hashomer, to Haganah, to IDF.

The Jewish paramilitary organisations in the New Yishuv (the Zionist enterprise in Palestine) started with the Second Aliyah (1904 to 1914). The first such organization was Bar-Giora, founded in September 1907. It consisted of a small group of Jewish immigrants who guarded settlements for an annual fee. At no time did Bar-Giora have more than 100 members. It was converted to Hashomer (Hebrew: השומר‎‎; "The Watchman") in April 1909, which operated until the British Mandate of Palestine came into being in 1920. Hashomer was an elitist organization with narrow scope, and was mainly created to protect against criminal gangs seeking to steal property. During World War I, the forerunners of the Haganah/IDF were the Zion Mule Corps and the Jewish Legion, both of which were part of the British Army. After the Arab riots against Jews in April 1920, the Yishuv's leadership saw the need to create a nationwide underground defense organization, and the Haganah was founded in June of the same year. The Haganah became a full-scale defense force after the 1936–1939 Arab revolt in Palestine with an organized structure, consisting of three main units—the Field Corps, Guard Corps, and the Palmach strike force. During World War II the successor to the Jewish Legion of World War I was the Jewish Brigade, which was joined by many Haganah fighters. During the 1947-48 civil war between the Arab and Jewish communities in what was still Mandatory Palestine, a reorganised Haganah managed to defend or wrestle most of the territory it was ordered to hold or capture. At the beginning of the ensuing 1948-49 full-scale conventional war against regular Arab armies, the Haganah was reorganised to become the core of the new Israel Defense Forces.

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