And where were the French expanding in 1815?

Er..Belgium?

"To the Belgians and the inhabitants on the left bank of the Rhine: The ephemeral success of my enemies detached you for a moment from my empire. In my exile, upon a rock in the sea, I heard your complaint; the God of Battles has decided the fate of your beautiful provinces; Napoleon is among you; you are worthy to be Frenchmen. Rise in a body; join my invincible phalanxes to exterminate the remainder of these barbarians, who are your enemies and mine; they fly, with rage and despair in their hearts."

The Palace of Laeken, June 17, 1815.