Strasbourg, German Strassburg, city, capital of Bas-Rhin département, Grand Est région, eastern France. It lies 2.5 miles (4 km) west of the Rhine River on the Franco-German frontier. History. The city was originally a Celtic village, and under the Romans it became a garrison town called Argentoratum. It was captured in the 5th century by the Franks, who called it Strateburgum, from which the present name is derived.