Which nation was called Persia until 1935?

Iran was the nation called Persia until 1935. The name Persia came from the Greek and later Western usage of Persis, a region in southern Iran associated with the ancient Persian Empire.

In 1935, Reza Shah Pahlavi's government asked foreign countries to use Iran, the name long used domestically and rooted in the Middle Persian term Ērān. The change applied to official international correspondence and reflected the country's broader national identity rather than only the historical region of Persis. Persia did not disappear from history: it remains a valid cultural and historical term, especially when discussing the Achaemenid, Sasanian, Safavid, and other Persian traditions.

A frequent misunderstanding is that Persia and Iran were entirely different countries. They refer to the same modern country, although Persia can describe particular historical periods, peoples, languages, and cultural traditions. The 1935 change also predates the 1979 Iranian Revolution, after which the country became the Islamic Republic of Iran. Today, Iran is the standard political and geographic name, while Persian remains widely used for the language and cultural heritage.