The Hôtel de la Guerre (Hotel of War) is an 18th-century government building in the town of Versailles that served as the Ministry of War under the ancien régime. Together with the Hôtel de la Marine and the Hôtel des Affaires Étrangères, it formed part of the administrative apparatus of the French state that operated from Versailles when it was the seat of government.
The building is historically significant as the site where the Treaty of Paris was signed on 3 September 1783, recognising American independence. The negotiations had taken place over months in Versailles and Paris, with Benjamin Franklin, John Adams, and John Jay representing the new United States. The signing room has been preserved, and the building occasionally opens for visits.
The Hôtel de la Guerre is part of the less-visited government quarter of Versailles, south of the palace, that housed the ministers and departments of a French state that operated entirely from this town for a century. Walking through this area gives a different picture of Versailles — not the court and its ceremonies but the bureaucracy that ran an empire.