"Grenville" -- as in Grenville Township, Grenville-sur-la Rouge Municipality and Grenville Village -- trace their name back to William Wyndham Grenville, a British statesman who served briefly (1806-1807) as British Prime Minister, during the time that Grenville Township was being established and surveyed.
Grenville-sur-la-Rouge, however, is a relatively new creation. It was formed in 2002 by the amalgamation of all the communities within Grenville Township including: Avoca, Bell Falls, Calumet, Grenville Bay, Kilmar, Marelan and Pointe-au-Chêne.
The name "Rouge" was added in to differentiate from Grenville Village and because the Rouge River runs from north to south roughly through the centre of the new municipality. Finally, "sur-la" acknowledges the Francophone culture and political landscape of the province. Translated to English, it means "Grenville-on-the-Rouge".
Historically, the Grenvilles were a prominent aristocratic family in the eighteenth and early nineteenth centuries, from the English county of Buckinghamshire. The family produced several national political figures, including two British Prime Ministers. William Wyndham Grenville’s father, George Grenville, had also served as Prime Minister, from 1763-1765.
William Wyndham Grenville entered the House of Commons in 1782, representing Buckinghamshire. He later served as Paymaster of the Forces (1784 -1789). In 1789, he served briefly as Speaker of the British House of Commons before he entered the cabinet as Home Secretary. He became Leader of the House of Lords when he was raised to the peerage in 1790, as Baron Grenville of Wotton in the County of Buckingham. For the next decade (1791-1801), he was Secretary of State for Foreign Affairs, during the tumultuous Wars of the French Revolution.
Grenville left office in 1801 over the issue of Catholic emancipation. In 1806, he re-entered politics and became Prime Minister as head of a coalition government. The issue of Catholic emancipation again arose and split his coalition, causing his government to collapse in March, 1807. A notable accomplishment during his short tenure as Prime Minister, however, was the abolition of slavery in the British Empire.