Historically, Iran has been referred to as Persia by the West, due mainly to the writings of Greek historians who referred to all of Iran as Persís meaning "land of the Persians", while Persis was one of the provinces of ancient Iran.

In 1935, Reza Pahlavi requested the international community to refer to the country by its native name, Iran. Opposition to the name change led to the reversal of the decision in 1959, and Professor Ehsan Yarshater, editor of Encyclopædia Iranica, propagated a move to use Persia and Iran interchangeably. Today, both Iran and Persia are used in cultural contexts, while Iran remains mandatory in official state contexts.

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