But we are concerned more particularly here with the origin of the motte-and-bailey castle. The exact place or time of its first appearance is still a matter of conjecture. Certainly there is not a word in the chronicles which is descriptive of this kind of castle before the beginning of the 11th century.[182] The first historical mention of a castle which is clearly of the motte-and-bailey kind is in the Chronicle of St Florent le Vieil, where, at a date which the modern biographer of Fulk Nerra fixes at 1010, we learn that this same Count of Anjou built a castle on the western side of the hill Mont-Glonne, at St Florent le Vieil, on the Loire, and threw up an _agger_ on which he built a wooden tower.[183] In this case the word _agger_ evidently means a motte. But Fulk began to reign in 987; he was a great builder of castles, and was famed for his skill in military affairs.[184] One of his first castles, built between 991 and 994, was at Montbazon, not far from Tours. About 500 metres from the later castle of Montbazon is a motte and outworks, which De Salies not unreasonably supposes to be the original castle of Fulk.[185] Montrichard, Chateaufort, Chérament, Montboyau, and Baugé are all castles built by Fulk, and all have or had mottes. Montboyau is the clearest case of all, as it was demolished by Fulk a few years after he built it, and has never been restored, so that the immense motte and outworks which are still to be seen remain very much in their original state, except that a modern tower has been placed on the motte, which is now called Bellevue.[186] It was a tempting theory at one time to the writer to see in Fulk Nerra the inventor of the motte type of castle, for independently of his fame in military architecture, he is the first mediæval chieftain who is known to have employed mercenary troops.[187] Now as we have already suggested in Chapter I., the plan of the motte-and-bailey castle strongly suggests that there may be a connection between its adoption and the use of mercenaries. For the plan of this kind of castle seems to hint that the owner does not only mistrust his enemies, he also does not completely trust his garrison. The keep in which he and his family live is placed on the top of the motte, which is ditched round so as to separate it from the bailey; the provisions on which all are dependent are stored in the cellar of the keep, so that they are under his own hand; and the keys of the outer ward are brought to him every night, and placed under his pillow.[188]