Socialist Zionism originated at the close of the 19th century and had to struggle for followers among Jewish socialists who rejected Zionism as a “reactionary movement.” Jewish socialists saw the solution of the Jewish problem in a Utopian world that socialism aimed to create for all people. The first Jewish leader to differ with the Marxist idea was Moses Hess, who held that Jewish people had the right to a place in humankind’s family of nations. As the Socialist Zionist movement grew, it had to make its way against socialist ridicule and opposition. Nachman Syrkin and Ber Borochov were the leaders in this struggle. Syrkin saw in Socialist Zionism a modern expression of the Hebrew prophets’ teachings of justice for all. He founded the first Poale Zion, or Workers of Zion, group in London in 1903. Borochov felt that the special problem of the Jewish masses could be solved only in a Jewish Socialist commonwealth in Palestine. At a conference in 1906, the various Russian Poale Zion groups reconciled their differences and formed the Jewish Social Democratic Party, Poale Zion of Russia. This body united with the Poale Zion groups of Austria and the United States in 1907 to form the Poale Zion Party as an autonomous body within the World Zionist Organization. The Labor Zionists came to Palestine as the famous pioneering Second Aliyah (1904-1914), which established agricultural cooperatives and organized the self-defense that guarded Jewish colonies from Arab attack. Before World War I, the Labor Zionists were divided into two parties: Poale Zion and the Hapoel Hatzair, or the Young Worker. The personality and “religion of labor” gospel of Aaron David Gordon exerted the greatest influence on both groups. The Poale Zion leaders in Palestine included David Ben-Gurion, Yitzhak Ben-Zvi, and Berl Katznelson. In 1929, Poale Zion and Hapoel Hatzair merged to form Mifleget Poale Eretz Israel, the Party of the Workers of Israel. For decades, Mapai, the initials by which this party is known, was the largest political party in Israel. (See also Hashomer Ha-tzair.)