According to legend, Zarathustra's mother came from Raga. In modern research there is disagreement about Zarathustra's birthplace and his place of activity, which is why several possibilities are controversially discussed. By Touraj Daryaee (USA) Balkh in the north of today's Afghanistan is given as birthplace.
Northeast Iran and Sistan
Hints in the Avesta are interpreted in the form that Zarathustra could have stayed in Sistan (in today's border area of Iran and Afghanistan). Sistan played an important role in the Persian world of faith, which, however, cannot be causally attributed to Zarathustra. Only in post-Zarathustrian times the attempt to establish connections and commonalities took place, because due to the isolated desert location the holy mountain Kuh-e Hadsche at Lake Hamun made the place Sistan the Mecca of the Zoroastrian followers.
Through many periods of Sistan's history, the oasis led a life of its own because of its difficult-to-reach location and developed completely autonomously, detached from the respective religious currents. Because of Sistan's religious appeal, it is therefore probable to a small degree that Zoroaster may have temporarily worshipped here, although evidence of early Ahuramazda belief in this region is lacking. However, because of the documented early Iranian migration from east to west, short-term points of contact may have existed.
Media and Azerbaijan
In the regions of the Median confederation, the originally Persian state territory of Parsua is documented in Assyrian inscriptions as early as around 1000 BC. In the following period, it is mentioned increasingly frequently under the name of Anshan. Archaeological investigations confirm decisive political and social upheavals for the same period in the territory of present-day Azerbaijan. Among other things, Azerbaijan was the destination of east-west migration, in the course of which East Iranian nomads migrated alongside Indian tribes. The archaeological evidence shows that the indigenous culture intermingled with that of the new immigrants.
In connection with the settling down and the merging of the nomadic culture with the agricultural culture, there are also clear indications of the development of a new religion. In the 8th century B.C. the Median name Mazda appeared for the first time, which only lacked the addition Ahura. Zarathustra also never mentioned the name Ahuramazda in his teachings, but at first only Mazda or Ahura. It should be reserved to the Achaemenids to unite both names to Ahuramazda only in 522 B.C. under Darius I.
The name component Wischtaspa (horse) refers to the horse breeding areas characteristic of Media and Azerbaijan, from which the Assyrians obtained their horses. Zarathustra called among others the Median priestly caste Magawan his followers, whose heartland was without doubt Azerbaijan.