Built in 1705 as the residence of then-governor of Montreal, Claude de Ramezay, the Château was the first building proclaimed as a historical monument in Quebec and is the province's oldest private history museum.

[1][2] Over the years, the Château changed owners and functions several times, with Ramezay's descendants selling the manor to the fur-trading Compagnie des Indes.

The building was bought by the Numismatic and Antiquarian Society of Montreal and converted into an historical museum and portrait gallery in 1894.

From 1997 to 2002, the Château Ramezay underwent indoor and outdoor restorations, including the creation of the Governor's Garden, inaugurated in 2000.

In 2003, the Château Ramezay Museum earned the National Award of Excellence from the Landscape Architects of Canada.