The Chambre introuvable (French for "Unobtainable Chamber") was the first Chamber of Deputies elected after the Second Bourbon Restoration in 1815. It was dominated by Ultra-royalists who completely refused to accept the results of the French Revolution. The name was coined by King Louis XVIII of France.
The "Unobtainable Chamber", which was first assembled on 7 October 1815, was characterized by its zeal in favour of the aristocracy and the clergy and aimed at reestablishing the Ancien Régime. The Chambre introuvable voted the establishment of military provost-marshal courts and banished all of the Conventionnels who had voted for Louis XVI's execution.
Louis XVIII, confronted with rising discontent in French society, followed the counsels of the Duc de Richelieu, prime minister since September 1815, the Duke of Wellington, the British commander of the occupation troops, and the Russian ambassador Pozzo di Borgo, and dissolved the Chamber on 5 September 1816.
The subsequent elections resulted in the Ultras being temporarily replaced by the more liberal Doctrinaires, who attempted to reconcile the Revolution's legacy with the monarchy.
When under the government of Jean-Baptiste, comte de Villèle, the Ultra-royalists resumed the majority in the chamber in December 1823, this chamber was dubbed "Chambre retrouvée", the "Recovered Chamber", in reference to the Chambre introuvable.