David Ben-Gurion was the primary national founder of the State of Israel and the first Prime Minister of Israel. Adopting the name of Ben-Gurion in 1909, he rose to become the preeminent leader of the Jewish community in British-ruled Mandatory Palestine from 1935 until the establishment of the State of Israel in 1948, which he led until 1963 with a short break in 1954–55.
Ben-Gurion's passion for Zionism, which began early in life, led him to become a major Zionist leader and executive head of the World Zionist Organization in 1946. As head of the Jewish Agency from 1935, and later president of the Jewish Agency Executive, he was the de facto leader of the Jewish community in Palestine, and largely led its struggle for an independent Jewish state in Mandatory Palestine. On 14 May 1948, he formally proclaimed the establishment of the State of Israel, and was the first to sign the Israeli Declaration of Independence, which he had helped to write. Ben-Gurion led Israel during the 1948 Arab–Israeli War, and united the various Jewish militias into the Israel Defense Forces. Subsequently, he became known as "Israel's founding father".