"" ("TOS)", which ran from 1966 to 1969, modeled the conflict between the Federation and the Klingon Empire on the Cold War (1947–1991), a period of geopolitical tension between the Western countries and the Soviet Union. "TOS" Klingons were not given many cultural traits, either unique or Soviet-like, beyond a generic need for domination and tyranny. However, they were typically portrayed with bronze skin and facial hair suggestive of North Asian peoples such as the Mongols (in fact, Gene L. Coon's only physical description of them in his "Errand of Mercy" script is "Oriental, hard-faced").