the von in a German or Austrians name means "of", it was also designated as a sign of rank, more or less like being knighted. so for example the Napoleonic era Prussian general August von Gnesinau...
Heinrich von Herzogenberg was born on June 10, 1843.
Heinrich von Herzogenberg died on October 9, 1900 at the age of 57.
Heinrich von Kleist was born on October 18, 1777.
Heinrich von Stephan was born on January 7, 1831.