The Great Turkish War started in 1683, with a grand invasion force of 140,000 men marching on Vienna, supported by Protestant Hungarian noblemen rebelling against Habsburg rule. To stop the invasion, another Holy League was formed, composed of Austria and Poland (notably in the Battle of Vienna), Venetians and the Russian Empire, Vienna had been besieged by the Ottoman Empire for two months. The battle marked the first time the Commonwealth and the Holy Roman Empire had cooperated militarily against the Ottomans, and it is often seen as a turning point in history, after which "the Ottoman Turks ceased to be a menace to the Christian world". In the ensuing war that lasted until 1699, the Ottomans lost almost all of Hungary to the Holy Roman Emperor Leopold I.