The Mauryan art is believed to be inspired from Achaemenid or Persian influence. We can find a lot of similarities in terms of form and style in the inscriptions of Ashoka and the Persian king Darius.
The Divyavadana is a Sanskrit anthology of Buddhist avadana tales. They have originated in Mulasarvastivadin vinaya texts. It is dated to 2nd century CE.
The Nanda dynasty ruled in northern part of the Indian subcontinent during the 4th century BCE, and possibly during the 5th century BCE. In 326 BC, Alexander invaded India, after crossing the river Indus he advanced towards Taxila.