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Chairman of the Presidium, or Presidium Chairman, was the official title held by Anastas Mikoyan during his brief tenure as the de facto head of state of the Soviet Union from 1964 to 1965. This position placed him as the ceremonial leader and presiding officer of the country's collective leadership body, the Presidium of the Supreme Soviet, responsible for overseeing state functions and representing the Soviet Union in official capacities.