The Iranian peoples or Iranic peoples are a diverse Indo-European ethno-linguistic group that comprise the speakers of the Iranian languages. Proto-Iranians are believed to have emerged as a separate branch of the Indo-Iranians in Central Asia in the mid 2nd millennium BC. At their peak of expansion in the mid 1st millennium BC, the territory of the Iranian peoples stretched across the Iranian Plateau and the entire Eurasian Steppe from the Great Hungarian Plain in the west to the Ordos Plateau in the east. The Western Iranian Persian Empires came to dominate much of the ancient world at this time, leaving an important cultural legacy, while the Eastern Iranian nomads of the steppe played a decisive role in the development of Eurasian nomadism and the Silk Route. Ancient Iranian peoples in