The Congress of Vienna convened to re-map post-Napoleonic Europe and prevent the rebuilding of a strong France. By February 1815, delegates from the European great powers and several other European countries had, through heated compromises, created a new map of Europe. Amongst other provisions, Russia retained most of the Napoleonic duchy of Poland (called ‘Congress Poland’), but could not unite it with the parts of Poland Russia had already acquired in the 1790s. The Republic of Cracow, a city-republic created by the Congress of Vienna, included the city of Cracow and its surrounding area, and was controlled by Russia, Prussia and Austria. It became a centre for Polish nationalist agitation. Prussia received the province of Posen and most of Saxony, as well as parts of the Rhineland and northwestern Germany. The new border states of the Netherlands were created as a buffer zone to France. Germany was turned into a confederation of 39 states, replacing the Holy Roman Empire, with the number of German principalities streamlined from 360 to 38. Switzerland was made into a neutral territory, while Austria was given several Alpine territories, Lombardy and the Dalmatian coast. Great Britain was given several overseas territories. In March 1815, Napoleon escaped from exile in Elba, but was decisively defeated at Waterloo, leading to further territorial changes under the Peace of Paris in June 1815.