Treaty of Athis-sur-Orge

The Treaty of Athis-sur-Orge was a peace treaty signed on June 23, 1305 between King Philip IV of France and Robert III of Flanders. The treaty was signed at Athis-sur-Orge after the Battle of Mons-en-Pévèle and concluded the Franco-Flemish War (1297-1305).

Based on the terms of the treaty, Walloon Flanders, being the cities of Lille, Douai, and Orchies, were allocated to the French crown. In return, Flanders was allowed to preserve its independence as a fief of the kingdom.