Cohors prima Raetorum equitata ("1st part-mounted Cohort of Raeti") was a Roman auxiliary mixed infantry and cavalry regiment. It is named after the Raeti nation, which dominated the eponymous province Raetia, which comprised much of modern Switzerland and Germany south of the river Danube. The Raeti originally spoke a non Indo-European language closely related to Etruscan. However, by the time their territory was annexed by Rome under founder-emperor Augustus (16 BC), they had become largely Celtic-speaking through contact with neighbouring peoples such as the Vindelici. Finally, during the centuries of Roman rule, they became Latin speakers: their distinctive provincial patois survives today in the form of the Rhaeto-Romance languages.