He negotiated diplomatic and marriage alliances with various dynasties which enabled him to strengthen his empire.
Step-by-step explanation:
Chandragupta Maurya married the Licchchavi princess of Vaishali with which he became the ruler of ancient Magadha kingdom. Mauryan empire expanded in the whole of India up to modern day Pakistan. He prevented the side if the Ganges from the invasions of Alexander.
He also married Nandini of Nanda empire which increased his influence in that kingdom and ultimately defeated the Nanda empire. After teh death of Alexander, all his kingdom were divided into satrapies. Chandragupta Maurya was able to defeat all the kingdoms in central Asia and extended kingdom up to Iran and Kyrgyzstan.