Naw Ruz (NouRooz, NowRuz) is a Persian national festival which celebrates the Iranian New Year. Unlike many other festivals in Persia, Naw Ruz is not exclusive to one religious group. The date of Naw Ruz is determined by the solar calendar and begins on the first day of spring. The festival lasts for thirteen days and is a time of renewal and joy.
The origins of Naw Ruz are uncertain. Some attribute the festival to the legendary king Jamshid and his victory over demon hosts. Others believe the celebration to be of agrarian origin and associate it with a fertility cult of ancient Near and Middle Eastern regions. However, the ancient and Zoroastrian Persia provides the richest historical detail.