the map on the left should show you where people still speak a variety of Sanskrit even today

 https://www.google.com/search?q=when+was+sanskrit+spoken&rlz=1C5CHFA_enUS750US750&oq=when+was+sanskrit+spoken&aqs=chrome..69i57j0i512j0i22i30l2j0i390l4.7441j0j7&sourceid=chrome&ie=UTF-8

in India Still Largely Speak Sanskrit ...

mapsofindia.com

Maps of Indo-European Languages-Sanskrit

Maps of Indo-European Languages-Sanskrit

web.cn.edu