Rottweil was founded by the Romans in AD 73 as Arae Flaviae and became a municipium, but there are traces of human settlement going back to 2000 BC. Roman baths and a mosaic of Orpheus (ca. AD 180) date from the time of Roman settlement. The present town became a ducal and a royal court before 771 and in the Middle Ages it became a Free Imperial City in 1268.
In 1463 the city joined the Swiss Confederation, with which it was closely aligned for several centuries. Both its status as free city and its alliance with the Swiss Confederacy were eventually lost with the conquest of the region by Napoleon in 1803. The appearance of the town changed very little from the 16th century.