Drawing on the correspondence of contemporary rulers and diplomats and on the work of modern European and American historians, this article reinterprets the origins of the War of the Spanish Succession by examining the triangular relationship between Leopold I, Louis XIV and William III during the last quarter of the seventeenth century. It disposes of two ‘myths’: namely that Leopold I and William III were natural allies and that Louis XIV and William III were natural enemies. During the Dutch War and the Nine Years War, relations between the allies William and Leopold were strained for various reasons. And although William regarded Louis XIV as his main rival after the Peace of Nijmegen (1678), at Rijswijk (1697) his relationship with Louis improved significantly. This resulted in two treaties between Louis and William partitioning the Spanish Empire after the death of Carlos II. Leopold I, who took no part in the treaty negotiations, refused to accept the second treaty, which widened the rift between him and the stadholder‐king. As William III refused to force Leopold I to accept the second treaty, Louis XIV accepted Carlos II's will, which left the Spanish inheritance to Philip of Anjou, Louis's grandson. When Louis XIV started to behave like a Spanish king and invaded the Spanish Netherlands, whose independence was the cornerstone of William's foreign policy, a rapprochement between Leopold and William took place, leading to the renewal of their former alliance and the outbreak of the War of the Spanish Succession.