NOWRŪZ (lit., "new day"), the Iranian national festival that celebrates the arrival of spring. A festival of renewal, hope, and happiness, Nowrūz begins on the first day of Farvardīn, the first month of the Iranian solar calendar, at the spring equinox, and continues for twelve days. It is the most widely celebrated, the longest, and the most colorful of Iranian festivals, and though inherited from Zoroastrian Persia, it is the only festival that is not confined to a single religious group.

The origins of Nowrūz are obscure. In popular legend its institution is associated mostly with Jamshēd, the mythical Iranian king. In Firdawsi's epic, the Shāh-nā mah (completed about 1000 CE), it is said that the feast commemorates Jamshēd's ascent into the skies in a chariot built by the demons whom he had subdued and forced...