E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
After me the Deluge [Après moi le Déluge]. When I am dead the deluge may come for aught I care. Generally ascribed to Prince Metternich, but the Prince borrowed it from Mme. Pompadour, who laughed off all the remonstrances of ministers at her extravagance by saying, Après nous le déluge (Ruin, if you like, when we are dead and gone).