John III of Brabant’s Marriage and the Breakdown of Franco-Brabant Relations (1311–1316)

As part of a gesture of rapprochement with France, Duke John III of Brabant married Marie d'Évreux (1303–1335) in 1311. Marie was the daughter of Count Louis d'Évreux and Margaret of Artois, making her the niece of King Philip IV of France. This dynastic alliance was meant to strengthen ties between Brabant and France, but tensions quickly emerged.

French Demands and Brabant’s Refusal (1316)

• In 1316, the new French king, Louis X, sought to use Brabant as an ally against Flanders, a long-standing rival of the French Crown.
• He demanded that Brabant cut off trade with Flanders and participate in a French military campaign against the rebellious Flemish.
• However, the Brabantine councilors, representing the duchy’s powerful merchant towns, found this demand impossible to fulfill, as Brabant was economically dependent on trade with Flanders, particularly its textile and commercial networks.

Louis X’s Retaliation and Violation of Treaty Terms

• In reprisal for Brabant’s refusal, Louis X prohibited all French trade with Brabant in February 1316, dealing a major economic blow to the duchy.
• This move violated a treaty of friendship that Louis had personally signed with Brabant in October 1315, further souring relations.
• The embargo highlighted the growing conflict between Brabant’s economic interests and French royal ambitions, demonstrating that marital alliances alone could not override economic realities.

Impact and Legacy

• The failed alignment pushed Brabant toward a more neutral or anti-French stance, as it needed to maintain commercial independence from France.
• The duchy increasingly positioned itself as a key player in the Low Countries, balancing between the competing influences of France, the Holy Roman Empire, and Flanders.
• The conflict foreshadowed Brabant’s later role in resisting French centralization efforts while continuing to profit from its powerful mercantile economy.

John III’s marriage alliance with France (1311), though politically strategic, failed to secure long-term Franco-Brabant relations, as economic priorities ultimately overrode dynastic ties.