An international team is using Geographic Information Systems (GIS) modelling to assess Julius Caesar's account of his war with a Celtic tribe. According to Caesar, more than a quarter of a million Helvetii were settled in the Swiss plateau before they decided to abandon their territory and invade Gaul in 58 BCE. In his Gallic Wars he says the Helvitii were running out of food. UWA archaeologist Tom Whitley is developing a GIS model to test Caesar's population estimate and is testing geophysical techniques to see if they can detect signs of the migration and war. He is using the...