The day October 8 in Ancient Iran is the beginning of Mehregan celebrations or Festival which had root in Mehr Creed, one of the oldest Iranian festivities which were held since Oct. 8 to Oct. 13. Mehr or Mitra in old Persian has the meaning of light, brightness, friendship, consistency and kindness and against perfidy. By the order of Dariush the Great, the Achaemenian king, the Iranian schools started the school year on 23 September. This became a basis that the beginning of school year across the world be set between September 1st to October 1st. The great Iranian poet Ferdowsi described in his famous book Shahnameh the origin of Mehregan Celebration as the victory of people in Kaveh Ahangar’s fight against a despotic king Zahhak.