The Shahnameh is a 50,000 verse epic poem written by the Persian poet Ferdowsi, started in 977 and finished in 1010. Its name translates as Book of Kings, and that's basically what it is: A recounting of the Persian kings from the creation of the world to the Arab conquest. Most of these kings are mythical, though. The closer the narrative gets to the time of Ferdowsi's writing, the more historically accurate it becomes.