Crédin is a commune in the Morbihan department of Brittany in north-western France. Inhabitants of Crédin are called in French Crédinois…Crédin is a commune in the Morbihan department of Brittany in north-western France. Inhabitants of Crédin are called in French Crédinois. The canal de Nantes à Brest, which is the canalized river Oust, forms the commune's eastern border.