Gādhi's Son

Viśvāmitra came of the line of Kuśa, a son of Brahmā, the creator. Kuśa's son was Kuśanābha, a king devoted to dharma, the right way of living. Kuśanābha had no son, and he held a sacrifice to have one, and while it was going on his father Kuśa told him that a son would be born to him equal to him in goodness, through whom he would win lasting fame. That son was Gādhi. Gādhi's son was Viśvāmitra, and because he was born in the line of Kuśa he was called Kauśika. The line of Kuśa is also called the line of Kuśika, and so he is called the son of Kuśika too.

He had an elder sister named Satyavatī, who kept her vows strictly. She was married to the sage Ṛcīka, followed her husband faithfully, and in time went to heaven in her own body and flowed out as a great river, the Kauśikī, divine and full of holy water, along the foot of the Himālaya, for the good of the world. Viśvāmitra loved her, and for her sake he lived in peace on the slopes of the Himālaya beside her waters.

Before any of that he was a king, and a good one. He was a kṣatriya, born to the warrior class that kings come from, and not a brahmin, born to the priestly class. He ruled the earth for many thousands of years, keeping dharma, learned and devoted to the welfare of his people.