 The river Slack flows through the commune, as does the A16 autoroute.Part of the Flemish-speaking territory until 1346, Marquise became an English county under King Edward III after the battle of Crécy and the hexagonal bell-tower goes back to the English period.In 1420, in the suburbs of Marquise, at Leulinghen, the church of which was divided by the French-English border, King Henry V married Princess Katharine, daughter of Charles VI of France.