In July, 1488, he came suddenly down upon Brittany, took one after the other Chateaubriant, Ancenis, and Fougeres, and, on the 28th, gained at St.Aubin-du-Cormier, near Rennes, over the army of the Duke of Brittany and his English, German, and Gascon allies, a victory which decided the campaign: six thousand of the Breton army were killed, and Duke Louis of Orleans, the Prince of Orange, and several French lords, his friends, were made prisoners.

On receiving at Angers the news of this victory, Charles VIII.

gave orders that the two captive princes should be brought to him; but Anne de Beaujeu, fearing some ebullition on his part of a too prompt and too gratuitous generosity, caused delay in their arrival; and the Duke of Orleans, who was taken first to the castle of Sable and then to Lusignan, went ultimately to the Tower of Bourges, where he was to await the king's decision.
It was a great success for Anne de Beaujeu.

She had beaten her united foes; and the most formidable of them all, the Duke of Orleans, was her prisoner.

Two incidents that supervened, one a little before and the other a little after the battle of St.Aubin-du-Cormier, occurred to both embarrass the position and at the same time call forth all the energy of Anne.