Breton March

The Marches of Neustria were two marches created in 861 by the Carolingian king of West Francia Charles the Bald that were ruled by officials appointed by the crown, known as , prefects or margraves (or "marquis" in French). Originally, one March was created against the Bretons and one against the Norsemen, often called the Breton March and Norman March respectively.

In 911, Robert I of France became margrave of both Marches and took the title demarchus. His family, the later Capetians, ruled the whole of Neustria until 987, when Hugh Capet was elected king of the Franks. The subsidiary counts of Neustria had exceeded the margrave in power by that time and the peak of Viking and Breton raiding had passed. After the Capetian Miracle, no further margraves were appointed.

The original march of Brittany was created and militarized under the Merovingians in the late 7th or early 8th century. Although its exact extent is unknown and its boundaries do not coincide with the later Breton March; it included the Rennais and Nantais territories (French: pays), and parts of the Vannetais and Maine. Administration centered in Le Mans and the territory eventually went by the name of ducatus Cenomannicus or Duchy of Maine. One of the most famous margraves ("Britannici limitis praefectus") was Roland, who died at the Battle of Roncesvalles in 778 and gave rise to a famous series of legends as exemplified in the eponymous Chanson de Roland.

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