Indo-Roman relations began during the reign of Augustus (23 September 63 BCE – 19 August 14 CE), the first emperor of the Roman Empire. The presence of Romans in the Indian Subcontinent and the relations between these regions during the period of the Roman Empire are poorly documented. Unlike the earlier conquests of Alexander in the Indian subcontinent, there are no surviving accounts by contemporaries or near-contemporaries, so modern understanding depends on more abundant literary, numismatic, and archaeological evidence, mainly relating to the trade between them.