<P> In the Western world, Persia (or one of its cognates) was historically the common name for Iran . On the Nowruz of 1935, Reza Shah Pahlavi asked foreign delegates to use the term Iran, the endonym of the country, in formal correspondence . Since then, in the Western World, the use of the word "Iran" has become more common . This also changed the usage of the terms for Iranian nationality, and the common adjective for citizens of Iran changed from "Persian" to "Iranian". In 1959, the government of Mohammad Reza Shah Pahlavi, Reza Shah Pahlavi's son, announced that both "Persia" and "Iran" could officially be used interchangeably . However the issue is still debated today . </P> <P> The name "Irān" is first attested in the Avesta as airyānąm (the text of which is composed in Avestan, an old Iranian language spoken in northeastern Greater Iran, or in what are now Turkmenistan and Tajikistan). </P>

What is the name of modern day persia