Mapping the PastMAP 3.2 The Mauryan Empire, ca. 250B.C.E. The Ganges River Valley was the heart of the Mauryan Empire. Although India is protected from the cold by mountains in the north, mountain passes in the northwest allowed both migration and invasion.ANALYZING THE MAP Where are the major rivers of India? How close are they to mountains?CONNECTIONS Can you think of any reasons that the Persian Empire and Alexander’s conquests both reached into the same region of northwest India?