Florimund Mercy, Count d'Argenteau (1727-1794): Marie-Antoinette mother's spy

Florimund Mercy was an Austrian minister in Paris, and was used to strengthen the alliance of France and Austria. Mercy was one of Maria Theresa's closest ambassadors and used  to spy on her and give all of the information to Maria Theresa. 

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http://en.wikipedia.org/wiki/Florimond_Claude,_Comte_de_Mercy-Argenteau

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