Answer:In 327 BCE, Alexander of Macedon and his troops entered India and overran the existing kingdoms in the Punjab region. He left after only two years, but his destruction of the regional powers opened the opportunity for other groups to seize control. The first group, the kingdom of Magadha, used their military to gain control of trade routes through the Ganges valley and the sea routes to the Bay of Bengal.
Soon after, however, Chandragupta Maurya, the founder of the Maurya Empire, successfully seized control of Magadha. He started on the outskirts and eventually made his way to the heart of the kingdom. Eventually, he gained control of northwestern India and Bactria—what is today Afghanistan and was at that time controlled by the Greeks. Chandragupta Maurya successfully unified the Indian subcontinent under an empire.
Step-by-step explanation: