The first great indigenous empire to spread over most of present-day India, Pakistan, and Bangladesh was the Mauryan Empire (ca. 320-180 BCE), whose most famous ruler was Asoka (ca. 273-232 BCE).

Although the empire was well administered and politically integrated, little is known of any reciprocal benefits between it and eastern Bengal.

The western part of Bengal, however, achieves some importance during the Mauryan period because ships sail from its ports to Sri Lanka and Southeast Asia.

During the time of the Mauryan Empire, Buddhism comes to Bengal, and it is from here that Asoka's son, Mahinda, carries the message of the Enlightened One to Sri Lanka.

After the decline of the Mauryan Empire the eastern portion of Bengal becomes the kingdom of Samatata; although politically independent, it is a tributary state of the Indian Gupta Empire (CE ca.  319-ca. 540).