Darius III
According to Arrian, Indian troops were still deployed under Darius III at the Battle of Gaugamela (331 BCE). He explains that Darius III "obtained the help of those Indians who bordered on the Bactrians, together with the Bactrians and Sogdianians themselves, all under the command of Bessus, the Satrap of Bactria". The Indians in questions were probably from the area of Gandara. Indian "hill-men" are also said by Arrian to have joined the Arachotians under Satrap Barsentes, and are thought to have been either the Sattagydians or the Hindush.