Some challenges remained. France was hit by civil unrest known as the Fronde which in turn evolved into the Franco-Spanish War in 1653. Louis II de Bourbon joined the Spanish army this time, but suffered a severe defeat at Dunkirk (1658) by Henry de la Tour d'Auvergne. The terms for the peace inflicted upon the Spanish kingdoms in the Treaty of the Pyrenees (1659) were harsh, as France annexed Northern Catalonia.