The Château de Montsoreau is a Renaissance style castle directly built in the Loire riverbed in the small market town of Montsoreau, in the Maine-et-Loire département of France, in close proximity to Saumur, Chinon, Fontevraud-L'abbaye et Candes-Saint-Martin. The château de Montsoreau has an exceptional position at the confluence of two rivers, the Loire and the Vienne, and at the meeting point of three historic regions: Anjou, Poitou and Touraine.
A Gallo-Roman origin has been verified for the settlement of Montsoreau but not confirmed for the castle, even though a fluted column made of stone from a Gallo-Roman temple or a public building was found in the moat during the restoration works of the end of the 20th century. The first written sources are from the 6th century with the domain of Restis, but it is only with the construction of a fortress at the end of the 10th century that the market town began to become prosperous. One part of this first castle was found during the same restoration works by the archaeologists. The castle was reconstructed in a Renaissance style between 1450 and 1460 by Jean de Chambes, one of the kingdom's wealthiest men, a senior councillor and chamberlain to King Charles VII and to King Louis XI.
The Château de Montsoreau was immortalised by Alexandre Dumas in his novel La Dame de Monsoreau written between 1845 and 1846. This novel is the second part of a trilogy on the Renaissance, between La Reine Margot and Les Quarante-cinq.
Unlike others châteaux of the Loire Valley, Montsoreau is the only one that is actually built in the Loire riverbed.
The Château de Montsoreau was listed as a monument historique by the French Ministry of Culture in 1862. The Loire Valley between Sully-sur-Loire and Chalonnes has been inscribed as a UNESCO World Heritage Site since 30 November 2000.