A few days after Santanu was born, the river goddess Ganga met King Pratipa in the forest and told him of her love for Santanu. She said that she had fallen in love with Santanu even before he had entered the womb of Pratipa's queen and asked to marry him. So, Pratipa promised her that Santanu would be hers when he was old enough.
When Santanu was a youth, Pratipa told him that if were to meet a lovely maiden in secret near the Ganges, he was to take her as his wife. ``I gave her my word soon after you were born,'' the old king said to his son. The son promised to honor his father's word. Many years passed and King Pratipa died.
After Pratipa's death, Santanu became the king of the Bharatas and ruled from Hastinapura. One day, as he rode along the Ganges, he came across a beautiful woman dressed in shimmering blue silk. Then and there, he proposed to her: ``Whatever race you are, O Beautiful one, whether you be Naga or Apsara or human like me, be my queen.''
Ganga blushingly accepted his proposal but extracted a promise from the smitten king. ``You must never ask me my name or who I am or why I do the things I do. The day you ask me such a question, I shall leave you.''
Santanu, the king, agreed and married Ganga. Every year, for eight years, Ganga bore Santanu a son. The moment the son was born, however, she would take the baby to the river and drown it. In all other respects, she was a wonderful wife and Santanu bore her inexplicable behavior for seven years. The eighth year, however, the good king could bear it no longer.
``Stop!', he cried, ``cruel woman, why do you so kill your own sons?''
Ganga then reminded him of his promise not to ask her any questions. ``I will have to leave you now,'' she said, ``but first let me tell you why I killed the seven children born to us.'' She told him that the eight sons they had had were the eight Vasus, cursed by Vashishta to be born into this earth for stealing his cow . ``This eighth child,'' she said, ``is Prabhasa who was the one who actually stole the cow. He is cursed with living a long and full life on earth.''
``I will bring him to you when he is a young grown boy,'' she promised King Santanu and disappeared into the Ganges.
Several years later, Santanu was walking along the Ganges when he noticed a young boy, building a dam of arrows across the Ganges in flood, playing with the mighty river as a child plays with a loving mother. The king was standing transfixed with awe when Ganga rose from the waters and presented the youth to Santanu.
``This is your son Devendra,'' she told him, ``he equals Parasurama in prowess. He has learned the Vedas from Vashishta and the sciences from Sukra. Take back with you this talented child.''
So saying, Ganga disappeared leaving Devendra with your ancestor Santanu. The king took Devendra back to Hastinapura and crowned him heir apparent.
Years went by and one day Santanu was walking in the forest when drawn by the fragrance of flowers in a season where there are none, he came upon the beautiful Satyavati . He asked this woman in whose presence the air was so sweet to be his wife. She said she would accept him but that he should ask her father for his consent.
The fisherman was not about to let his daughter become just another of the king's harem. ``Promise me that my daughter's children will be your heirs and this fragrant daughter of mine is yours,'' he said. The king of course could make no such a promise since Devendra was the heir apparent.
Santanu returned to Hastinapura downcast and when Devendra asked him what was wrong, he said cryptically: ``life is uncertain and in this world where all things are transient, having one son is the same as having no sons at all.''
Devendra was not the son of Ganga for nothing. He understood what was going on and asking the charioteer where the king had been that morning, made his way to the fisherman's abode. The fisherman told him the same thing that he had told Santanu.
Devendra immediately promised that he would not lay any claim on the throne of Hastinapura. ``The sons of my mother here,'' he said, ``will be the kings of Hastinapura.''
The fisherman was not satisfied. ``You may make these promises, O Prince but what if,'' he asked, ``your sons lay a claim on the throne? They will be warriors like you and all your glory will attach to them. What then of the grandchildren of a fisherman?''
It was then that Devendra took his terrible vow. ``I shall never marry,'' he vowed, ``I dedicate my life to chastity.'' When Devendra took this terrible vow of Brahmacharya, even the gods showered flowers on his head and from that day on, he was known as ``Bhishma'', which means one who fulfills a terrible vow.
Confident now that his daughter would be a mother of kings, the fisherman relented. His daughter Satyavati became queen of Hastinapura. She bore the king Santanu two sons, Chitrangada and Vichitravirya.