The castles in the immediate neighbourhood of Angers were mostly in the hands of John or his friends; there was, however, one important exception--La Roche-au-Moine,[887] where William des Roches, now seneschal of Anjou for Philip Augustus, had lately built a fortress to protect the road between Angers and Nantes against the garrison of Rochefort, whose commandant was a partisan of John.[888] To La Roche-au-Moine John laid siege with all his forces on June 19. The siege had lasted a fortnight[889] when Louis advanced from Chinon to relieve the place, then on the verge of surrender. At the tidings of his approach John sent out scouts to ascertain the strength of the enemy; they returned with the assurance that the English king had an overwhelming advantage in numbers, and was certain to be victorious if he engaged the French in a pitched battle. John was eager for the fight;[890] so, according to the French historiographer-royal, was Louis, who sent to his rival a public challenge, which John as publicly accepted.[891] But the “wonted treachery”--as an exasperated English writer calls it--of the Poitevins overthrew his hopes. According to one account, “the barons of Poitou, disdaining to follow the king, said that they were not ready for a fight in the open field.”[892] According to the French version of the story, the immediate author of John’s discomfiture was the veteran turncoat Almeric of Thouars, who, it seems, addressed John in a most insulting manner, mocking at his eagerness for battle, insinuating that it was mere boastfulness which the king would never carry out in act, and then made it impossible for him to do so, by withdrawing himself and all his followers from the host.[893] Whichever version be the correct one, the consequences were inevitable; John could not risk an encounter with Louis after such a revelation of treason in his own ranks. In rage and grief he broke up the siege {July 2}, and hurried away to the south side of the Loire.[894]