Let me explain to you how things really happened in the simplest way possible.
You see, A country called Iran didn't exist till a century ago and nobody in the world knew Iran. There wasn't a single evidence in all of history books, Nor a single reference in any of historical sites that pointed out the country of Iran existed. So when Pahalvi dictatorship, The poppet of the west, Wanted to created the country of Iran in an Islamic land so the westerners can steal the oil and the resources, He wanted a fake history so he can legitimize his rule over the land and trick the non Persian people into submission, So with the help of the Jews he gathered the history books from all around the world and put some fake history in them and then, As
@mohsen said, With the help of British forces they made some fake historical artifacts here and there, And suddenly the country of Iran was born!
And now, Sadly people are so brainwashed that they still believe in those lies.