The collection of towers was linked by curtain walls and formed a true "closed-town" lordly castle. Charles VIII concretely set his sights on the duchy of Brittany by the capture of Guingamp on 10 January 1489 by the viscount of Rohan and his troops. Concerned for Brest, duchess Anne directed the lord of Kérousy to reinforce it, but the castle opened its gates to the viscount of Rohan (doubtless aided by the treason of the castle's captain). Like her predecessors, Anne initially allied herself with England. She returned Concarnaeu and Brest to Henry VII of England and the new Anglo-Breton alliance led to 22 vessels blockading Brest by sea and a strong army with high-quality artillery besieging it by land. However, the marshal of Rieux and admiral Bizien de Kérousy had to give way before the forces sent under Guillaume Carreau to defend Brest. A French squadron under Graville and reinforced by the Malouins of Jean de Porcon, put an Anglo-Breton fleet to flight and re-supplied the besieged castle. Harassed by the French, Rieux had no choice but to abandon it. As a sign of his sovereignty, Charles VIII ordered that the French coat of arms be placed below the ravelin's gate. Anne of Brittany's marriage to Charles VIII on 6 December 1491, then to Louis XII of France on 17 January 1499, definitively put the castle under French royal control. In April 1505, the French king was gravely ill and Anne, his queen, decided to make a pilgrimage in the month of August to ask for his recovery. Her procession left Blois for Brittany. Her squire Gilles of Texue accompanied her, as did princes and lords of France and Breton barons and gentlemen. Anne began on the Tro Breizh, a pious pilgrimage for Bretons around Brittany, visiting seven cathedrals dedicated to their founding saints and inspecting her domains and fortifications as she passed from town to town and castle to castle - Nantes, Vannes, Hennebont, Quimper, Locronan. Jean d'Auton wrote in his chronicles of Louis XII that:  Arriving at Le Folgoët on 19 August, the end of her pilgrimage, Anne showed a desire to continue to Brest and contemplate the powerful castle that her father Francis II had embellished and modernised and the large nef "Marie La Cordelière", one of the largest warships of the era.