The earliest mention of the Udras or Odras or Audras as a people is, perhaps, found in the sloka of the Manavadharma-sashtra where the Odras are classed as outside the Brahmanical pale along with the Paundrakas, Dravidas, Kambojas, Yavanas, Paradas, Pahlavas, Cinas, Kiratas, Daradas and Khasas. A Pali Cannon has mentioned that Oddaka who were the same as Odra, or Udra.
Some historians have said that Odras were people of India in whose country stood Mount Maleus. In many places it has been claimed that Odras were people who belonged to the land of Orissa. On the other hand epic tradition connects the Udras along with the Pondras, Utkalas, Mekalas, Kalingas and Andhras.
According to the Brahma Purana the country of the Odras extended northwards to Vrajamandala (Jajpur), and consisted of three kshetras called Purushottama or Srikshetra, Savitu or Arkakshetra, and Birajakshetra through which flew the river Vaitarani. But nowhere in early inscriptions there is any mention of the people and their country. The first elaborate account of the people and their country is found in the itinerary of Huen Tsang.
History has recorded that the Odras were of violent ways, tall and of dark complexion, in speech and manners different from the people of central India. They were indefatigable students and many of them were Buddhists. There were around 100 Buddhist monasteries and many Buddhist followers in the land of the Odras. Most of the Buddhists among the Odras were Mahayanists. There were around 50 deva temples in the country of Odras and near the shore of the ocean in the south-east of this country was the city of Charitrapura.
It has been referred by several historians that about a century later the country of the Odras became involved in chaos. Along with the land of the Odras five other countries of the esat had plunged them into political chaos and they were rescued from the situation by King Gopala.
It has been said that Odda-visaya is certainly identical with Odra-visaya and during the thirteenth century when King Rajewndra Chola had conquered the land of Odda-visaya it came to mean the whole of the present Orissa country.
