After Alexander went back to Babylon in 324 BC, a man named Chandragupta was able to overthrow the old Aryan kingdom of Nanda and form a big new empire over all of northern India and into Afghanistan. When people asked him how he had done it, he said (according to Greek historians) that he got the idea from Alexander. Chandragupta conquered the Indus valley back from the Greeks and as part of the peace treaty he married the daughter of Seleucus, who had succeeded Alexander.
The Nanda King, Dhanananda, had by his tyrannical ways created many enemies, and one of these, a proud and fiery man of the high Brahmin class whom he had thoughtlessly insulted in Court, was to soon enough cause his ruin. This was Chanakya, who, under the pseudonym Kautilya, later wrote the famous political book 'Arthashastra'. An unforgiving opponent, he had vowed not to tie his hair in the customary Brahminical top-knot until he had avenged his insult. This didn't particularly worry Dhanananda what could a single Brahmin do anyway? He exiled him from Pataliputra and considered it the end of the matter.
The advent of the Mauryans brought them into conflict next with the Greek General Seleucus I Nicator, who had inherited both Alexander's Asian holdings and his Empire-building dreams. These, Chandragupta shattered in 303 B.C. The resulting treaty gave the loser 500 war-elephants and granted to the victorious Changragupta the Seleucid Provinces of Trans-Indus (Afghanistan), Seleucus's daughter Helen in marriage, and the future Court presence of the Seleucid Ambassador Megasthenes. The latter's fascinating account of his tenure, 'Indika', has survived in fragments down the centuries.
