The last veda called the Atharva Veda is a collection of magic spells and charms to ward off the evil spirits and diseases. It is considered a non-Aryan work and is the latest addition to the Vedas in later Vedic age.
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.