Zarathustra is the only monotheistic prophet in the Iranian land. He is described as a wise and clear-sighted man and an exceptional orator by characters in the Iranian epic poem Shahnameh (Book of Kings) written by Abolqasem Ferdowsi.
The dates of his life and the beginning of his religious mission are not clear. Some scholars believe his emergence was about 6000 years before Plato or around the time the Iranian King Xerxes entered Greece, while others place him about 5000 years before the Trojan War which occurred 6100 B.C. Thus the dates of his lifetime vary between 600 to 6000 years B.C. The Iranian Zarathustrians, relying on Zabih Behrooz's account, believe Zarathustra's birth date was 1768 B. C.
In the Avesta, the sacred book of Zarathustrianism, the prophet's birth place is called Regeh on the River Darji near lake Chichist which is supposed to have been on the west of Lake Urmiye according to some scholars, while others believe the place was near Rey City, close to Tehran. The prophet's name occurs as Zarat Ustra which is supposed to mean bright star, glittering light, clear-sighted and wise. The best translation would seem to be "bright light". He is supposed to have been killed during prayer in the city of Balkh, while by some accounts he passed away peacefully among his family.

Rituals

In the Gathas it is enjoined that one should say prayer with uplifted arms, clean body, serene mind and a joyful heart. This is recommended as a means of getting close to Ahura Mazda and for the purpose of being in harmony with the essential mode of being "Asha" (good deed). During the Sassanid period, when part of the Minor Avesta was edited on the initiative of Maraspand, five daily prayer times were regulated.
Ancient Iranians, inspired by the teachings of their prophet Asha Zarathustra, were of the opinion that happiness was one of the manifestations of Ahura Mazda and that it resulted from being in harmony with life. Thus they tried to dispel sorrow and mourning from their lives on every occasion.
Nowrooz, the New Year, is the most important and most splendid Iranian tradition. Occurring on the vernal equinox, it is celebrated with great festivities.
In the Zarathustrian calendar the 16th day of the month of Mehr (October 8) is named after Mehr (Mithra) and it was celebrated before the calendar was altered.
There are three views regarding the origin of the Mehrgan feast. According to one view it is the day God Almighty inspired the living spirit into the body of "Mashi" or "Mashianeh" (the first human being). Then there is the view that the date commemorated people's revolt against the cruel rule of Zahhak. Led by the blacksmith Kaveh, they enchained Zahhak in Mount Damavand. A third tradition regards the feast as the anniversary of the day Ardashir Babakan wore the crown with the emblem of the sun.
Another feast "Chaharshanbeh Souri" (fireworks Wednesday), is a spring rite celebrated on the last Wednesday of the year. (1)
The feast of "Sadeh" or "Sadak", which occurs on January 30, is the feast of fire. People created fire and smoke to drive away evil spirit and wild animals. They also flew birds among the flames and children played around the flames.
According to one tradition about then origin of the feast, it is the anniversary of the accidental discovery of fire by King Hushang. When the monarch threw a stone at a black snake, the stone hit another stone (apparently both were flint stones) and there was a spark which drove away the snake. King Hushang thanked God for having revealed the secret of fire to him, and set the date as the occasion for a feast.
Another view considers the feast as the anniversary of the day when the children of Kiumars, father of mankind, numbered 100. It is also stated that the word "sadeh" meant creation in the ancient Persian and the feast is regarded as a celebration of the 40th day of the birth of "Yalda", the sun.
Other Zarathustrian feasts are the feast of lightning, the feast of the green day, and the feast of Spandar Madh.

History

According to Shahnameh, Zarathustra and his religion appeared during the reign of Gushtasb. Zarathustra appeared in the royal court and proclaimed his religion. King Gushtasb embraced Zarathustra's teachings which basically ensure well-being and lofty values for human beings. The exact circumstances under which King Gushtasb accepted Zarathustrianism is not known. Guided by the instructions of Zarathustra, people started more civilized modes of managing the general affairs of the country, the development of cities and construction of religious buildings, including fire temples.
Zarathustra personally planted a cedar tree in Mehr Barzin Temple and recorded on the tree trunk the king's acceptance of his religion. This is also mentioned in Ferdowsi's Shahnameh:

He inscribed on the tall cedar that Gushtasb embraced the right religion.

He made a testimony on the cedar that wisdom spreads justice.

As the cedar grew to a great height a palace was built near it on which were painted images of patriotic and just monarchs like Jamshid and Freydoon. In the Shahnameh the tree is mentioned as the Kashmar Cedar. There has never been anywhere a tree similar to the cedar planted by Zarathustra.
The monarch of the country asked the courtiers, the aristocracy and all high officials to visit the Kashmar Cedar planted by the prophet and follow the ways of life preached by him and give up the worship of the Chinese idols.
Thus the heavenly tree, which is known as the Kashmar Cedar, became the first emblem of Zarathustra's religion and the start of the spread of his teachings in the country. Zarathustra became the king's guide and mentor in following the path of spirituality, good deeds, good words and goodthought.
According to historical texts, especially Ferdowsi's Shahnameh, Iran paid toll to China during the reign of Gushtasb. Zarathustra was against paying tribute to a foreign country and succeeded in convincing Gushtasb that this was beneath the dignity of a free nation and thus managed to make the king end the foreign domination.
Gushtasb's brother, Zarir, and the king's son, Esfandiar the great warrior, undertook the task of promoting the new religion in towns and cities and achieved great success in establishing the new creed throughout the country.
As the number of adherents to the new religion grew, the country became known as the land of Zarathustra, a fact that is reflected in the past literature and poetry.

Beliefs

Fravahar in the Zarathustrian creed is one of the spiritual powers with which God invests man at the moment of birth, and it returns to the spiritual sphere after death.
Amesha Spandan are God's attributes. The six Divine attributes are good thought, truthfulness, power, affection, communication and eternality.

Pilgrimage

Fire temples are the Zarathustrian sacred places where the burning fire symbolizes the Divine Light. Temples were built in uniform structures which included eight doorways, with several octagonal chambers surrounding a courtyard with a brazier of everlasting fire. With the subsequent doctrinal revisions it was believed that the sacred fire should not be exposed to sunlight and so the fire braziers were placed under arched roofs. There were numerous fire temples in the country in ancient times and some of them had been built even before the time of Zarathustra. In the Sassanid period, however, three fire temples ? Azar Goshasb (in the Tekab region), Azar Barzin Mehr and Azar Farnabagh ? had prominent positions.
The fire burning in temples in Iran, Pakistan, or India is a reminder of a culture of several millennia. All through the ups and downs of history the Zarathustrians kept the fire burning to the present time. For instance, the fire burning at Atash Bahram (Uduada) Temple just a 100 kilometers from Mumbai and usually referred to as Iranshah, is the same fire the Iranians took to India after the Sassanid period and was permanently stationed in Uduada after several changes of site.
Among the present day burning fires, the Chak-Chak Temple (Pirsouz) in Yazd, and the Kerman Temple deserve mention. The temple in Yazd is 1500 years old.

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1. Dr. Kurosh Niknam, the Zarathustrian priest and a scholar on ancient Iranian rites and traditions, believes Chaharshanbeh Souri has nothing to do with ancient Persia and that it was introduced in Iran after the Arab invasion. Ancient Persians did have seven-day weeks. They called each day of the month by the name of an angel. For Arabs Wednesdays were ominous days and that should prove that the custom of lighting fireworks on the last Wednesday of the year originated from the Arab culture.
2. The image of Fravahar incorporates the fight between the two symbols of Spanta Minio (goodness) and Angra Minio (evil). Fravahar's humanlike face indicates the deity's relationship with man. He resembles an old man and thus emphasizes the wisdom and experience of the old age.
The two lateral wings carry three prominent feathers, symbolizing good thoughts, good word and good deed. And the three lower wings symbolize wrong thoughts, wrong words and wrong deeds which are sources of mankind's misery and suffering.
There are two rings, one in front of the face and the other behind the head and symbolize respectively Spanta Minio and Angra Minio and indicate that one should always move toward goodness and move away from evil.
A third ring around the upper body symbolizes the eternal existence of the Spirit.
One of Fravahar's hands is raised toward the sky as a sign of praise of Ahura Mazda and the need for the purification of the soul. A ring which Fravahar carries in the other hand is, according to some commentators, the sign of a covenant and the truthfulness which is one of the basic tenets of Zarathustrianism.