Located on the bank of the canal from Nantes to Brest, Guenrouet turned to green tourism. Several restaurants have the gastronomic reputation of the town. Fish are the most popular of these tables.
Ancient parish, established around 1000, its territory was subject to the authority of many lords throughout the Middle Ages to the Revolution (seigneuries Fersnay to Plessé, Baron de Pont-Château and Roche Bernard, lord of Lévrisac and Nail).
During the Revolution, the village has a revolutionary party in the rectory and became the chief town of the canton. But because of lack of zeal Republican population (many refractory priests to the religious policy of the Republic are protected) and disorders due to the Chouans, he loses the privilege.
The construction of the canal from Nantes to Brest under the July Monarchy promotes the economic development of the municipality.
In the 19th century until the eve of the First World War, Guenrouet experienced a period of prosperity (it houses more than 3500 inhabitants) and in many artisans.
The two world wars had a profound place in the death of many people and the bombing of the pocket of Saint-Nazaire (destruction of churches and Guenrouet Our Lady of Grace and the three bridges across the canal) in August 1944 to May 1945.
