As the author states in his Introduction, this volume ""falls into the category of 'scientific-popular', to use current Russian terminology. This means that a general subject is presented for students and the public, but that the treatment is based on the latest scholarly work..."" Richard N. Frye is Professor of Iranian at Harvard. He has produced a history of ancient Persia which is different from previous ones, in that he attempts to show ""the remarkable continuity of culture"" from the earliest beginnings down to and including the ""Islamicisation"" of the country in the tenth century AD. Several other new approaches are employed, notably as regards the knotty problems presented by Zoroastrianism, but his foremost concern has been to maintain ""a dispassionate approach to partisan theories."" The result is a solid, readable history of a place and its people of which most Americans today have, at best, a very uneven knowledge. Most of us are familiar enough with the names of Cyrus, Xerxes, Darius; but our view of their careers is Greek- or Hebrew-oriented. This book supplies the internal cultural context without which no real comprehension of their significance is possible.