sentences:  Its later name, originally "Constantia", comes either from the Roman emperor Constantius Chlorus, who fought the Alemanni in the region and built a strong fortress around 300 AD, or from his grandson Constantius II, who visited the region in 354.The remains of the late Roman fortress "Constantia" were discovered in 2003.Around 585 the first bishop took up residence in Konstanz and this marked the beginning of the city's importance as a spiritual center.