I wonder if this quote is apocryphal. I have seen it attributed to several other European figures. The only one that comes to mind at the moment is Count Schwarzschild, Austrian Foreign Minister who came in after Metternich fled during the 1848 Revolution. Schwarzschild had to call on Russia to intervene in Galicia and Hungary to prop up the Hapsburgs, and an aid lamented that Austria would be sorely in debt to the Tsar. Schwarzschild replied that Austria would astonish the world with its ingratitude.

I love that quote. Would that it were true. But I think it was originally attributed to Metternich, referring to Austria’s reaction to the military intervention of its ally, Russia, to quell the Hungarian uprisin of 1848.

Just to correct the correction, the person who made the comment was Prince Felix Schwarzenberg.

https://www.museumofhoaxes.com/hoax/weblog/degaulle_ingratitude/

"In 1945 did Charles De Gaulle really say to Winston Churchill, in reference to the military aid that the Allies provided to France to defeat Germany, that "We shall stun you with our ingratitude"? Monday, November 22 was the birthday of De Gaulle, and a number of right-leaning blogs marked the occasion by posting this quotation (they seem to have picked it up from an article in the Belfast Telegraph). So did De Gaulle really say this?

Even though the tense verbal exchanges between De Gaulle and Churchill are well known, this particular remark sounded hoaxy to me. A quick google search didn’t turn up any source that could verify the remark, though it did pull up an essay noting that Churchill once quoted to De Gaulle a passage from Plutarch: "ingratitude towards great men is the mark of a strong people." So it’s possible that De Gaulle responded to this comment by saying that the French would stun Churchill with their ingratitude (in which context, the remark would be a compliment).

However, a second, more thorough google search revealed that the ’stunning ingratitude’ quotation has been attributed to a number of other people besides De Gaulle. This 2003 article in theage.com.au attributes it to the prime minister of the Hapsburg Empire: When, in 1848, Tsarist Russia intervened to put down an insurrection in Hungary, thus saving the Hapsburg Empire which was then in deep trouble, the Hapsburg prime minister commented that: "We shall astonish the world with our ingratitude."

But quite a few other people (including the conservative columnists Pat Buchanan and George Will) credit the remark to the Italian statesman Camillo Benso Cavour: The Sardinian minister who guided his country to the unification of Italy in the mid-1800, Cavour, did so with French help in a war with Austria. Without the French Army the Austrians would probably still have been ruling Northern Italy in 1914. Cavour’s comment was that someday the Italians would astonish the world with their ingratitude to France.

I suspect that Cavour is the true source of the saying. In which case, it’s ironic that a remark originally referring to ingratitude towards France has now come full circle and is being used to demonstrate (supposedly) the ingratitude of France."

Apologies for above, seem to have screwed up the formatting.