Neustria

The territory of Neustria or Neustrasia, meaning "new land", originated in 511, made up of the regions from Aquitaine to the English Channel, approximating most of the north of present-day France, with Paris and Soissons as its main cities (which is roughly the current size of England and Wales). Thus Neustria formed the western part of the kingdom of the Franks under the rule of the Merovingian dynasty during the sixth to eighth centuries.

The distinct area originated at the time of the death of Clovis I (as well as the conquered territories over Syagrius), when his sons divided his lands between them. It later became a term for the region between the Seine and the Loire rivers known as the regnum Neustriae, a constituent subkingdom of the Carolingian Empire and then West Francia. The Carolingian kings also created a March of Neustria which was a frontier duchy against the Bretons and Vikings that lasted until the Capetian monarchy in the late tenth century.

Neustria was also employed as a term for northwestern Italy during the period of Lombard domination. It was contrasted with the northeast, which was likewise called Austrasia, the same term as given to eastern Francia.

Read more about Neustria:  Merovingian Kingdom, Carolingian Subkingdom, Carolingian March, Historiography