Greek control over the area along the Indus weakened after the withdrawal of Alexander and certainly after his death in 323 B.C. This unstable state of affairs must have provided Chandragupta Maurya with an opportunity to conquer and annex the territories of the northern kingdoms. Once established, he moved into central India and occupied the region north of the Narmada. But lasting peace was established in the north-west only by 303 B.C. with a treaty with Seleucus.
Magadha was being ruled by the Nandas at this time. It is said that Chandragupta began his march towards Magadha by small scale attacks on outlying villages. This strategy occurred to him when he saw a woman scolding her child for eating from the middle of the dish first, which was the hottest portion, rather than from the edges. Thus once the peripheral regions had been subdued he could converge on the centre. These conquests were achieved and consolidated largely through military strength. Classical sources stress the importance placed by Chandragupta on the army and mention staggering figures as its total strength.