The Cambridge History of India, Vol. I: Ancient India v1.c27.31

v1.c27.31

At this point the Indian tradition takes leave of Chandragupta and his mentor. The latter, his vow of vengeance accomplished, returns to his Brāhman hermitage. For Chandragupta the ensuing years must have been strenuous. The great military progress of Seleucus, whereby he sought to consolidate the eastern part of his dominions, brought him to the Indus about the year 305. He found Chandragupta, now master of all Hindustān, awaiting him with an immense army. For Seleucus the task proved too great: he crossed the Indus, but either no battle ensued, or an indecisive one. Seleucus was content to secure a safe retirement and a gift of 500 elephants by the surrender of all the Greek dominions as far as the Kābul valley. Upon these terms a matrimonial alliance was arranged¹.