The Batavians or Batavi were a Roman-era Germanic people that lived in Batavia in the eastern Rhine delta — an area that is now in the Netherlands, but then lay upon the northernmost border of the Roman Empire in continental Europe. The Roman author Tacitus said that they originated as a group of Rome-allied Chatti, who settled in Batavia around 50–15 BC. Archaeological evidence shows that they joined a Celtic-influenced community that had already been living there long before the arrival of the Romans. Throughout the several centuries in which they appear in historical records the Batavians were continually associated with elite cavalry units in the Roman military, who were famous for their ability to cross rivers while armed and on horseback, without breaking line.