Polish king Jan III Sobieski delivered a great blow to the Ottoman forces at Vienna on 12 September 1683, never again allowing them to return to Central Europe. Austria and Poland concluded a union against the Ottomans in the spring of 1684 with Venice joining later. Russia also decided to become part of the coalition in 1686. The union this time sought the help of Bulgarian Catholics alone. It was noted by Bulgarian Bishop that over 500 Albanian Catholics in the region were involved in the Uprising against the Turks as well. The residents of Chiprovtsi and the neighbouring villages decided that the appropriate moment had come when the Austrian army took Belgrade on 6 September 1688.