During the Merovingian period, the western part of the kingdom of the Frank s after the 6th-century conquest by Clovis .
The eastern kingdom was Austrasia . Neustria corresponded roughly to the area of present-day France west of the Meuse River and north of the Loire River . The name later denoted a much smaller area; by the 11th12th centuries it was sometimes used synonymously with Normandy .