Alexander the Great chased the King of Persia (Babylon) and the General who killed the King all the way to the borders of modern day Afghanistan which was part of the kingdom of Chandra Gupta. Alexander and Gupta together engaged the Nagas, it was then Alexander got arrowed and returned to Babylon.
I doan think Persia ruled any regions of todays India. The ancient Persian border ran up to the kingdom of Chandra Gupta's kingdom.
I read somewher that when Alexander asked one of the tribal rulers he had defeated why they had put up such fierce resistance, he was told, in effect, "You ain't see nothing yet! Go further in!" So he turned back because his army was ready to mutiny! 'Dese fing peepul mad'!