The Kurds share their lands with other ethnic groups. Some of the Kurds' neighbours are Turks, Arabs, Persians, Jews, Armenians, and Assyrians. In the past, some Arabic and Turkic people became Kurds by cultural assimilation. In the nationalist period, the governments of the states that control Kurdistan tried to assimilate the Kurds into Turkish, Iranian, and Arabic culture. These states (Turkey, Iran, Iraq, and Syria) also moved Turks, Persians, and Arabs into Kurdistan. The governments of these states have used genocide, ethnocide, linguicide, and ethnic cleansing against Kurds. The Soviet Union also forced Kurds from the Caucasus to migrate to Central Asia. When the Soviet Union ended, the First Nagorno-Karabakh War between Armenia and Azerbaijan affected most of the Kurds in the Caucasus. 