Territorialism was a Jewish political movement calling for creation of a sufficiently large and compact Jewish territory (or territories), not necessarily in the Land of Israel and not necessarily fully autonomous.
Before 1905 some Zionist leaders took seriously proposals for Jewish homelands in places other than Palestine. Theodor Herzl's Der Judenstaat argued for a Jewish state in either Palestine, "our ever-memorable historic home", or Argentina, "one of the most fertile countries in the world". Many of the socialist Zionist groups were more territorialist than Zionist, such as Nachman Syrkin's Zionist Socialist Workers Party (the Z.S.).
The Jewish Colonization Association, created on 1891 by the Baron Maurice de Hirsch, was aimed at facilitating mass emigration of Jews from Russia and other Eastern European countries, by settling them in agricultural colonies on lands purchased by the committee, particularly in North and South America (especially Argentina).
In 1903 British cabinet ministers suggested the British Uganda Program, land for a Jewish state in "Uganda" (actually in modern Kenya). Herzl initially rejected the idea, preferring Palestine, but after the April 1903 Kishinev pogrom Herzl introduced a controversial proposal to the Sixth Zionist Congress to investigate the offer as a temporary measure for Russian Jews in danger. Notwithstanding its emergency and temporary nature, the proposal still proved very divisive, and widespread opposition to the plan was demonstrated by a walkout led by the Russian Jewish delegation to the Congress. Few historians believe that such a settlement scheme could have attracted immigrants, Jewish financial support, or international political support. Since there was strong support on the part of some members of the Zionist leadership, however, peace was kept in the movement by the time-honored parliamentary maneuver of voting to establish a committee for the investigation of the possibility, which was not finally dismissed until the 7th Zionist Congress in 1905.
In response to this, the Jewish Territorialist Organization (ITO) led by Israel Zangwill split off from the Zionist movement. It attempted to locate territory suitable for Jewish settlement in various parts of America (e.g. Galveston), Africa, Asia, and Australia, but with little success. The ITO was dissolved in 1925.
Apart from the (ITO), within the USSR there was also a Territorialist effort in Ukraine, the Crimea and then in a region surrounding Birobidzhan, where a Jewish Autonomous Region was established in 1934. (The Jewish Autonomous Oblast (JAO) (Russian: Евре́йская автоно́мная о́бласть, Yevreyskaya avtonomnaya oblast; Yiddish: ייִדישע אווטאָנאָמע געגנט, yidishe avtonome gegnt) is still today an autonomous oblast situated in Russia's far east.)
In the face of the looming Nazi genocide, Isaac Nachman Steinberg established the Freeland League in the United States in 1935. This organization attempted, unsuccessfully, to pursue Jewish autonomy by obtaining a large piece of territory in sparsely populated areas in Ecuador, Australia, or Surinam. One of the more well-known ventures was the Kimberley Plan, to secure land in Australia.  After the establishment of the State of Israel in 1948, Steinberg had criticized the exclusivist politics of the Zionist government and continued his attempts to create a non-nationalist Jewish settlement in some other region of the world. After Steinberg's death in 1957 the Freeland League was led by Mordkhe Schaechter, who gradually changed the focus of the organization to more cultural, Yiddishist goals.
The 2007 alternate history detective story "The Yiddish Policemen's Union" by American author Michael Chabon, inspired by the 1939 Slattery Report and based on the premise that after World War II, a temporary Yiddish-speaking settlement for Jewish refugees was established in Alaska in 1941 while the State of Israel was destroyed shortly after its creation in 1948, can be considered a Territorialist alternate history (though the writer does not necessarily share the ideology of the Territorialist movement).