The provided episode offers an overview of the Second Siege of Vienna in 1683 and the resulting Battle of Kahlenberg, a pivotal conflict that marked the beginning of the Ottoman Empire's decline. We detail the 61-day siege of Vienna, describing the desperate conditions inside the city and the arrogance of Sultan Mehmed IV and his Grand Vizier, Kara Mustafa. Further we explain the complex political negotiations needed to assemble the allied Christian relief army, led by the Polish King Jan III. Sobieski, whose cavalry delivered the decisive blow on September 12. Additionally we provide specific military details, including the composition and size of the German-Polish relief forces from various principalities like Saxony and Bavaria. Finally we also outline the course of the battle, emphasizing Kara Mustafa's strategic error in not securing the surrounding heights, and notes the significant casualties and historical reception of the pivotal victory.