The early Cold War saw the division of Europe and Asia between capitalist Western nations allied with the US and communist Eastern nations allied with the Soviet Union. This division hardened after WWII, as the USSR established satellite states across Eastern Europe separated from the West by an "Iron Curtain." The two sides pursued opposing economic and political ideologies in a global competition for power and influence that included proxy wars, arms buildups, and space races during the late 1940s-1980s until reforms under Gorbachev led to the dissolution of the Soviet Union and end of the Cold War.