Battle of Saint-Denis, the last battle of the Franco-Dutch War, fought on August 14, 1678, just days after the Dutch and France had signed a peace treaty. France had not made peace with Spain, so when France besieged Mons, in what is now Belgium, a Dutch-Spanish army engaged in battle. France triumphed, but was forced to abandon the siege.
The war had gone well for the French after the Battle of Agosta in 1676, and peace negotiations had begun that year. On August 10, 1678, the Dutch and the French made peace by signing the Treaties of Nijmegen. France had delayed making peace with Spain so it could capture Spanish-held Mons. The Dutch military commander, Prince William of Orange (later William III, king of England), was eager that France should not gain such a strategically important town. So, despite having knowledge of the recent peace, William marched toward the French army of Marshal François-Henri, Duke of Luxembourg, which was blockading Mons.
Luxembourg moved to challenge Orange and entrenched his army in two positions: in the abbey of Saint-Denis and in Castean, a ruined fortress. When battle started on August 14, the Dutch-Spanish army made good early progress and captured both French positions. During the fighting, two bullets pierced William’s armor, but he was not seriously injured. The French managed to recover their ground and force the allies back to their starting positions after eight hours of battle. Only determined resistance from 8,000 English and Scottish troops fighting for the allies prevented William’s army from being encircled completely. The next morning, Luxembourg decided to raise the siege, and his army withdrew back to France. William had not secured a victory, but his action had saved Mons from capture. France and Spain made peace the next month.
Losses: Dutch-Spanish allied, 4,000 of 45,000; French, 4,000.