Pre-history
Mythological stories claim that Bihar was the place where King Satyavrata (सत्यव्रत) resided after the flood in his kingdom, with the help of Vishnu-Avatar Matsya. A king of the Yadavs, nicknamed "Mahabali" ruled over this last in ancient times. He was impotent. His guru was Maharishi Dirghatamas. Mahabali had many wives and so Maharishi Dirghatamas with the permission of his king impregnated Mahabali's chief queen Sudeshna. Queen Sudeshna bore five children or "Kshetrajas" (rulers of lands), one of them was King Anga, which is modern-day Bihar. From Anga sprang Anapana.
According to the historian Asim Maitra, the history of Magadha from the earliest times to the dawn of the Buddhist age is not well known. The entire Vedic literature displays open hostility and disgust towards Magadha, because Magadha was a great stronghold of the pre-Aryans and refused to be absorbed in the stereotyped Brahmanical pattern. Before the discovery of the ruins of Mohenjodaro and Harappa, the cyclopen walls on the hills of Rajagriha were an ancient archaeological remains in India.
Read more about this topic: Bihari People