Franz Karl Ludwig Wilhelm von Hacke entered the service of his native Electorate of the Palatinate. He became a Privy Councilor and Government Councilor and also held the rank of Lieutenant Colonel. He was also a Knight of Malta and a Knight of the Wittelsbach Order of St. Hubert. Until his death, he succeeded his father, who died in 1752, as Chief Master of the Hunt, having previously held the office with him for a time.
On October 9, 1756, Elector Karl Theodor appointed the Baron as Electorate of the Palatinate's Ambassador and Minister Plenipotentiary in Vienna. At the outbreak of the Seven Years' War in 1756, negotiations for a protection treaty with Austria for the Duchy of Jülich were conducted through him.
Franz Karl Ludwig Wilhelm von Hacke was only able to hold this office for just under a year. On September 4, 1757, around 7 a.m., on his return journey from the Palatinate to Vienna, he was asleep in his carriage on board a ship traveling down the Danube. The ship struck the bridge near Kelheim, and Hacke fell overboard and drowned. Contemporary sources report that some of his luggage was recovered. This suggests that the entire carriage, with the sleeping ambassador, plunged into the river during the accident.
Source: Wikipedia