The day of Nowruz has its origins in the Iranian religion of Zoroastrianism and is thus rooted in the traditions of the Iranian peoples; however, it has been celebrated by diverse communities for over 3,000 years in Western Asia, Central Asia, the Caucasus, the Black Sea Basin, the Balkans, and South Asia.[30][31][32][33] Presently, while it is largely a secular holiday for most celebrants and enjoyed by people of several different faiths and backgrounds, Nowruz remains a holy day for Zoroastrians,[34] Bahá'ís,[35] and some Muslim communities.[36][37]

As the spring equinox, Nowruz marks the beginning of spring in the Northern Hemisphere,[26][38] i.e. the moment at which the Sun crosses the celestial equator and equalizes night and day is calculated exactly every year. Traditional customs of Nowruz include fire and water, ritual dances, gift exchanges, reciting poetry, symbolic objects and more; these customs differ between the diverse peoples and countries that celebrate the festival.[39]