The Kingdom of the Saguenay was a mythical land of vast riches believed to exist by early French explorers of Canada. Chief Donnacona told stories about it, claiming it had great mines of silver and gold, when he was imprisoned in France in the 1530s. The name Saguenay, from the legend, came to be applied to the Saguenay River.

Today, the Saguenay-Lac-Saint-Jean region of Quebec is sometimes referred to metaphorically as the Kingdom of the Saguenay (Royaume du Saguenay), for example in tourist marketing.

On an unrelated note, a micronational project in the Saguenay region, Le Royaume de L'Anse-Saint-Jean (q.v.), achieved a certain amount of prominence in 1997.