Interresting to know.

Anne Frédérique Ribaud Since a very long time, french was the principal lanquage in Europe, even in Vienna, Saint-Petersbourg, and other royal courts. When Prussian became a real independant state with Fréderic, and a real political strenght, the German language was adopted in Vienna. Catherine of Russia follow to speak french during a long time. And in 1789-1790, it was the begining of end of French use. I propose to you to read the memories of Prince de Ligne, Charles Joseh de Ligne, prince of Hainaut, belongs to Austria Empire, and served Habsbourg until his dead. He's born in 1735, died in Vienna in 1815, known a lot of european events. He was the owner of the Beloeil castle.