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What happened at the Battle of the Dunes in 1658?

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Jules, Cardinal Mazarin Jules, Cardinal Mazarin, detail of a portrait by Philippe de Champaigne; in the Musée Condé, Chantilly, France.

The Battle of the Dunes (June 14, 1658) was a decisive engagement during the Franco-Spanish War, resulting in a victory for French and British forces over the Spanish army near Dunkirk.1

Under the direction of Cardinal Mazarin, France had formed a strategic alliance with England in 1657, promising the port of Dunkirk to the British in exchange for their military support. During the battle, French troops led by Henri de La Tour d’Auvergne, vicomte de Turenne were reinforced by 6,000 British infantrymen sent by Oliver Cromwell.12

Despite the Spanish force's strong cavalry, Turenne successfully exploited the difficult terrain of the dunes. British veterans captured key fortifications, while French cavalry and British naval bombardment overwhelmed the Spanish positions. The defeat forced Spain to surrender Dunkirk and paved the way for the Peace of the Pyrenees in 1659, effectively ending the long-standing conflict between the two powers.12