His uncle Talleyrand sought a high position for Edmond . He could not rise in France , since Napoleon had banned all French heiresses from marrying outside the French nobility and since Talleyrand had fallen from favor in 1807 after his resignation as Foreign Minister . Thus , at the Congress of Erfurt in 1808 , he approached Tsar Alexander I of Russia for permission for a marriage between Edmond and Dorothea von Biron , as a reward for Talleyrand 's diplomatic services . Talleyrand was certain of gaining permission from the bride 's mother , since he was on friendly terms with her and since payment of her annual apanage was dependent on Russia
Congress of Erfurt
Congress of Erfurt
Edmond de Talleyrand-Périgord