A great stone Roman Catholic Saint-Denis Church was completed in 1796.
On November 23, 1837, Saint-Denis-sur-Richelieu was the site of the murder of British courier, Lieutenant George Weir by Patriotes. Subsequently, the Patriotes, calling themselves The Sons of Liberty based on the American model, won a battle here against the British Army that marked the official beginning of the Lower Canada Rebellion. Today, Saint-Denis-sur-Richelieu has a museum called the Maison nationale des Patriotes, an interpretation centre that presents a history of the Patriotes movement that was led by the villager's most famous resident, Wolfred Nelson.
On October 21s 2012, a monument to the memory of Louis-Joseph Papineau was unveiled in a park next to City Hall, along the river, by Québec Premiere Pauline Marois.
