Montjoie (Old French Munjoie) is the historical battle cry supposedly used under Charlemagne and later in the medieval kingdom of France, where it was at some point, presumably in the 12th century (Louis the Fat), extended to Montjoie Saint Denis, in reference to the Oriflamme battle standard which was originally kept in the Abbey of St. Denis.
Louis VI replaced the earlier banner of Saint Martin with the oriflamme of the Abbey of St. Denis, which floated about the tomb of St. Denis and was said to have been given to the abbey by Dagobert.