Ze'ev Jabotinsky (born Vladimir Yevgenyevich Zhabotinsky in 1880 in Odessa, Russian Empire, now Odesa, Ukraine) was a Revisionist Zionist leader, ideologue, journalist, poet, and founder of the Betar youth movement. Born into an assimilated middle-class Jewish family, his father Yevno was a wheat trader who died when Vladimir was six, and his mother Chava ran a stationery store; he had an older brother Myron who died in infancy and a sister Tereza who founded a girls' school in Odessa. Raised secularly, he attended Russian schools, showed early talent in languages and literature, studied Hebrew with Joshua Ravnitzky, and translated poetry into Russian as a teenager. He dropped out of school at 17 and studied law irregularly at Sapienza University of Rome from 1898 without graduating, embracing a bohemian lifestyle.

At 18, Jabotinsky began a brilliant career as a correspondent for Russian newspapers like Odesskiy Listok and Odesskie Novosti, using pen names such as 'V. Egal' and filing dispatches from Europe; he was arrested in Italy in 1902 for anti-establishment writings. Joining Zionism before the 1903 Kishinev pogrom, he founded the Jewish Self-Defense Organization in Odessa, adopted the Hebrew name Ze'ev ('wolf'), and promoted slogans like 'Better to have a gun and not need it than to need it and not have it!' and 'Jewish youth, learn to shoot!' He was a delegate to the 6th Zionist Congress (1903), co-edited Yevreiskaya Zhyzn (1904–), co-founded the Union for Rights Equality of Jewish People in Russia (1905), and served as Zionist Organization representative in Constantinople (1908–1914), editing Le Jeune Turc.

During World War I, he co-founded the Zion Mule Corps (1915) with Joseph Trumpeldor and served in the Jewish Legion (1916–1919), entering Transjordan in 1918 and earning an MBE in 1919. In 1920, amid Palestine riots, he was arrested for illegal weapons and sentenced to 15 years (pardoned that July). Elected to the Palestine Assembly of Representatives (1920) and Zionist Organization executive (1921), he split from mainstream Zionism in 1923 to found the Revisionist Zionist Organization (Hatzohar) and Betar movement in Riga, demanding a Jewish state on both banks of the Jordan River and advocating military strength. He established the Betar Naval Academy in Italy (1934), toured Europe in the 1930s for Jewish evacuation plans, proposed an Irgun revolt against the British (1939), and offered 130,000 Jewish volunteers to Churchill (1940).

In 1907, he married Joanna (Ania) Galperina (1884–1949); their son Eri (1910–1969) later joined the Irgun-affiliated Bergson Group and served in Israel's 1st Knesset. A liberal democrat and economic liberal, Jabotinsky affirmed equal rights for Arabs in his writings and a 1934 constitution draft, famously stating 'Every man is a king,' though he controversially proposed Arab transfer if needed and was blamed by some for the 1920 riots. His literary works include poetry, novels like Samson Nazorei (1927) and The Five (1935–36), screenplays, translations of Poe and Dante into Hebrew, and editing The Jewish War Front (1940) and The Story of the Jewish Legion. His writings form the ideological basis for the modern Israeli right and settler movement. He died of a heart attack in 1940 at a Betar camp in Hunter, New York, and was reinterred on Mount Herzl, Jerusalem, in 1964.