The true story of Dorothea of ​​Lieven, the diplomat princess. What was her influence? How did she act unofficially in favor of Europe? Was it the first in Europe? To talk about it, Stéphane Bern receives Christophe Juban, author of “Dorothée de Lieven, diplomat and icon of the European Concert” (Editions Michel de Maule)  Historically Yours is produced by Guillaume Vasseau.