Urban Legend: Pravda got Checkov on Star Trek

The character of Ensign Chekov was added to the television series Star Trek because an editorial in the Communist newspaper Pravda had criticized the lack of a Soviet crewman on board the U.S.S. Enterprise.
We doubt Pravda actually did run an editorial about Star Trek, but we also doubt that even Gene Roddenberry would have forged a back-dated letter to support the claim that they did, so we think it likely he genuinely believed they had.
Urban Legends Reference Pages: Radio & TV (Russian Crewlette)