Thirty Years' War four-year period, the warring parties (the Holy Roman Empire, France, and Sweden) were actively negotiating at Osnabrück and Münster in Westphalia. The end of the war was not brought about by one treaty, but instead by a group of treaties such as the Treaty of Hamburg. On 15 May 1648, the Peace of Münster was signed, ending the Thirty Years' War. Over five months later, on 24 October, the Treaties of Münster and Osnabrück were signed. The war ranks with the worst famines and plagues as the greatest medical catastrophe in modern European history. Lacking good census information, historians have
War of the Fifth Coalition not been able to save Prussia. The Russian and French armies met in February 1807 at the savage and indecisive Battle of Eylau, which left behind between 30,000–50,000 casualties. Napoleon regrouped his forces after the battle and continued to pursue the Russians in upcoming months. The action in Poland finally culminated on 14 June 1807, when the French mauled their Russian opponents at the Battle of Friedland. The resulting Treaty of Tilsit in July ended two years of bloodshed and left France as the dominant power on the European continent. It also severely weakened Prussia and formed a Franco-Russian axis