Free Castle by Marc Morris Page B

the stone tower design, and built some of the most distinguished and important examples. Rochester, of course, was built by the Archbishop of Canterbury, while Conisbrough was built by Henry II’s half-brother Hamelin. The giant square keep at Kenilworth was built by the Sheriff of Warwick, and the vanished keep at Bungay was erected by the Earl of Norfolk. Several of these baronial towers were constructed during the reign of King Stephen, who, along with his rival Matilda, embarked on a policy of creating new earls in order to win support. Building a keep was an excellent way of proclaiming one’s own new-found importance, and there is good reason to think that it was recent ennoblement that inspired the building of towers at Hedingham and Castle Rising.
    When it comes to working out how much these castles cost, however, we have to rely on royal examples, because Crown records always survive much better than their aristocratic equivalents. For our detailed knowledge of costs in the twelfth century, we have to thank Henry I. Henry, when he wasn’t indulging his enormous sexual appetite (he had a string of mistresses before and after his marriage, and fathered at least twenty bastard children) was busy inventing new ways to govern the country. He is credited not only with the introduction of a new breed of administrative sheriff to manage his affairs in the English counties, but also with the creation of a new financial court to check on their activities. Twice a year, his sheriffs were obliged to come before the officers of this court and account for all the money they had received from rents, fines and taxes. The process was made easier with the help of a large visual and mathematical aid – a kind of abacus, with counters placed on a chequered cloth. Almost at once, people began to refer to the court as the Exchequer. When a sheriff was summoned before it, he either had to produce the money he owed, or give a good reason for its absence. One such good reason might be the building of a royal castle in the county at the king’s orders. Provided the sheriff could account for the money he had spent on building (produce receipts, if you like), the corresponding amount would be deducted from what he owed.
    Amazingly, the records of the Exchequer have survived. The clerks wrote up their accounts on huge parchment rolls, known as ‘pipe rolls’ (for the simple reason that, when rolled up, they looked like pipes). Using these ancient documents, we can find out rough costs for royal castles, and also gauge the length of time it took to build them.
    The sad thing is that although Henry I invented the whole accounting system, only one roll survives from his reign. As a result, we are not very well informed about the king’s castle-building activities. In fact, early twelfth-century towers – whether royal ones like Norwich, or baronial ones like Rochester – belong to a mysterious Dark Age, almost entirely unilluminated by written records. Fortunately, in Rochester’s case, we know from a copy of a royal charter that building began in 1127; and a Kentish chronicler noted in passing that the Archbishop of Canterbury began to construct ‘a noble tower’ at this time. But as to how long it took to build the mighty keep, and how much it cost, we can only make intelligent guesses by comparing it with examples from later in the century.
    From the start of Henry II’s reign, the pipe rolls survive in an almost unbroken series, and we can calculate the cost of some of the king’s keeps. The great tower at Dover, for example, which is shorter than Rochester but bigger at the base, cost around £4,000 and took ten years to build (1180–90). The much smaller keep that Henry built at Orford cost about £1,500 and took just six years to build (1166–72). With these figures in mind, and allowing for a small amount of inflation, the keep at Rochester must have cost at least £3,000, and taken between eight and ten years to