Why did Leopold I eventually join England and the Dutch Republic against Louis XIV?

Leopold I joined England and the Dutch Republic against Louis XIV primarily to counter the French king's aggressive expansionist policies, which threatened the stability of Europe and the interests of the Habsburg dynasty.12

Leopold’s decision was driven by several key factors:

• French Aggression: Louis XIV sought to exploit Leopold’s preoccupation with wars against the Turks by invading the Rhineland and devastating the Palatinate in 1688. This forced the Emperor to mobilize his forces in the west to defend German territories against French annexations.1
• Dynastic Interests: Leopold was deeply concerned with the future of the Spanish throne. As the Spanish king Charles II was childless, the inheritance became a central focus of Leopold's politics, aiming to maintain the unity of the House of Habsburg against the rising power of the Bourbon dynasty.123
• Strategic Alliances: Following the success of William of Orange in becoming King William III of England, Leopold concluded the Treaty of Vienna in 1689 with the United Provinces. This alliance sought to reverse Louis XIV's annexations and restore the peace settlements of Westphalia and the Pyrenees, forming the core of the Grand Alliance.1