[From Castle Rushen, Armitage Rigby, 1927]
HOUGH wanting in some of the more magnificent features of scenery so common to most parts of the Isle of Man, Castletown and its surroundings are peculiarly pleasant. The town has a delightful old world charm not yet destroyed by the ruthless hand of the Jerry builder, and the land surrounding it is the richest of all the fair lands of the kingdom of Man. Did not the holy Abbot of Furness in the year of our Lord 1134 mark it with unerring instinct as the most proper soil for the planting of his monastery of Rushen, selecting for his buildings a sheltered spot only two miles above the present town and on the bank of the Silverburn, which provided salmon for Fridays and water for the mill; and, indeed, much water would be needed to grind all the corn that might be produced on the rich lands he had chosen?
The chief owners of the district who signed the charter and probably gave up portions of their lands to form an estate fitting for so holy a purpose were Scandinavians, if we may judge from their names, sons of the hardy Norse islesmen who had helped Godred to conquer the island 55 years before, and to whom in return the rich lands of the southern part were granted; on such terms, however, "that no one of them should at any time venture to attach to himself by hereditary right any portion of the land, and hence it comes about that to this day the whole island belongs to the King alone."*
The names of these Norsemen are, perhaps, still preserved in the names of portions of their estates. The Reverend John Quine suggests that Thorkill is represented by Turkey land, between Ballasalla and the sea; Gil by Ballagilley around King William's College; Jol by Balladoole, now the property of the Stevensons; Fin by Fistard, near Port St. Mary; and Cutell by Kitterland, the islet between the mainland and the Calf Island.
But the reasons which induced Godred Crovan to grant the southern portion of the island to his followers, and the Abbot of Furness to choose the neighbourhood of Castletown for his spiritual offspring, would not be expected to weigh so heavily in the choice of a site for the chief fortress of the kingdom. Indeed the principle underlying the choice is far from clear at first sight, and can only be grasped by supposing that some alterations in the physical features surrounding the castle have taken place since the first stone was laid.
But before considering what changes may have taken place on the face of the earth, it may be wise to study the position of the castle as it is found at present, only ignoring the town which has grown around its walls 1st: What is the general value of the position? 2nd: Is it naturally strong or easily defended?
The first question naturally divides itself into the reasons for the choice, first of the district, and then of the particular spot. As argued in chapter xiii, the reason for the erection of a castle in this part of the island was probably the growing connection of the island with England; but the reason for the choice of the particular spot is by no means evident and needs careful study.
At the time when Castle Rushen was built the recognised landing place for this part of the island was Ronaldsway or Derby Haven, about a mile from the Castle; a snug little bay sheltered from the prevailing winds and in many ways suited to an age when even ships of war were beached. One would expect the Castle to be nearer to the landing place. If built to defend the island against invaders, it would surely be towering over the landing place, and if built as a foothold for the lord, a spot on the island to which he could go in safety if he heard that his subjects had revolted during his absence, and from which as a safe base he could commence operations against them, one would still expect it to be close to the port.
But we find it a full mile away, and in a position which does not seem naturally strong, certainly not so strong as positions which might have been selected on the shores of Derby Haven, for instance, St. Michael's Islet, which centuries later was chosen for the erection of a fort by the seventh Earl of Derby.
We may suppose then that Derby Haven was not considered a perfect harbour. It is certainly sheltered from the prevailing wind; but although much improved in recent times by the erection of a breakwater, it is still not entirely safe. The wind does not always blow from the prevailing quarter and in spite of the shelter afforded by the breakwater, shipwrecks on a small scale are by no means uncommon. Again those parts of the shore which afford suitable foundation for a castle are not suitable for the beaching of ships, so that they would have to be laid up some distance from the Castle walls, and would be subject to night attack.
But the very opposite conditions obtain in the position actually chosen for Castle Rushen. Though difficult and often impossible to make the harbour, once there, vessels could lie against the Castle wall, safe from the enemy and unaffected by any gale. This would be a matter of the greatest importance, and seems sufficient in itself to account for the choice of site. If, as seems probable, Olaf II chose the site, he would naturally be very careful to secure safe winter quarters for his fleet, for the destruction of his ships in 1228 by his brother Reginald would be ever fresh in his mind. This affair well illustrated the danger of wintering ships out of bow-shot of the Castle walls and in a harbour easily approached by sea. We read that " one midnight during winter, King Reginald came unexpectedly from Galloway with five ships (and) burnt during the same night all the ships of his brother Olaf and those of all the chiefs of Man at the island of St. Patrick."* Probably then the disadvantages of the dangerous entrance to Castletown harbour were considered to be more than balanced by its safety when once attained. No doubt Ronaldsway might often have to be used as the actual place of landing and possibly the earth work at Hango Hill represents a half-way fort or blockhouse for holding the road of approach but the first calm day would be utilised for bringing the fleet round to the shelter of the Castle walls. Another most important consideration was drinking water, which was plentifully secured on the site chosen, and would have been difficult to get in any suitable part of Derby Haven. And last, but not least, there was the river to carry out to sea all the rubbish and drainage of the Castle.
The above considerations seem to account for the choice of the site on general grounds, but the position leaves much to be desired in the way of natural strength, though were the ground always as at present, Castle Rushen would be by no means unique in weakness of position. The Tower of London is in a position similar in some respects, and no stronger, and many other examples might be cited, but they are generally in comparatively flat countries, whereas the Isle of Man abounds in rocky impregnable headlands such as would have delighted the architects of Chepstow and Edinburgh.
But if we go more closely into the matter we shall see that Castle Rushen held a stronger position when built than appears now. Sixteenth century maps of the island shew lakes and arms of the sea which no longer exist, but which are clearly indicated by low marshy ground, and the memory of them is not seldom preserved in the names of the lands occupying their sites or shores, while at least one of them is mentioned in the Chronicle of Rushen Abbey. Their disappearance is due to silting up and drainage. The largest of these lakes were probably in the north of the island, but in the south there are indications that there was a considerable sheet of water bounded by Balladoole, Ballakeighan, Billown, Great Meadow, and Red Gap; and another, being an enlargement of the Silverburn river, extending from the Castle wall to the mill weir, so that the land now occupied by Castletown was a portion of a promontory bounded on one side by the sea and almost cut off from the mainland in the rear by bogs and lakes, leaving a comparatively narrow approach along the line of the present Foxdale road. This causeway would probably be not more than a quarter of a mile wide at the narrowest part, and even if not defended by earthworks, would confine the enemy's approach to a known direction. In the seventeenth century there was a wall across, or partly across, this ridged in the middle of the present town. A portion of it still exists; and though what remains is evidently not earlier than the seventeenth century, it is quite probable that it represents the line of some earlier wall or fence. The part of Castletown immediately outside the wall is called The Crofts, and occupies the position, just outside the demesne boundary, where one would expect to find the crofts of a feudal establishment.
The marshes which flanked the approach to the Castle remind one of an old word-picture of Ely, which was described by the author of the " Acts of King Stephen" as " a pleasant island, extensive and well peopled, with a fertile soil and rich pasturage; it is surrounded on all sides by marshes and fens, and can be approached on one side only, where a straight and narrow road leads to the island and the Castle."
Instances of remarkable changes in the land surrounding fortified places are by no means uncommon. The town of Rye in Sussex is a well-known example; almost surrounded by the sea in the middle ages, it is now two miles distant from the water's edge. Again referring to the same county, the author last quoted says that Pevensey Castle, " built on an elevated mound, is surrounded by a stately wall, and is rendered impregnable by the sea which flows up to it, the tide filling the ditch, so that its position makes it almost inaccessible." In this case the sea is now more than a mile from the Castle. In the Isle of Man the same thing has occurred. Even to the casual observer it is evident that the valley between Peel and St. John's was comparatively recently a lake or arm of the sea, and the same is evident in respect of the land between Douglas and Kirk Braddan with its offshoot Port-e-Chee, " The harbour of peace"; and many other instances are familiar to those acquainted with the island. The Chronicle of Rushen Abbey seems to offer historical proof that the valley of the river Sulby was a tidal estuary or arm of the sea extending inland for some miles, as late at all events as the 11th century, for in the account of the battle of Scacafel we read that " when the natives saw that they were overpowered and had no means of escape (for the tide had filled the bed of the river Ramso, and on the other side the enemy was closely pursuing them), those who remained, with piteous cries, begged of Godred to spare their lives."* Had the battle occurred in the present year of grace, the retreat of the natives would not have been cut off and they might have retired rapidly to the Bride hills to reform in safety. For the river at the point where the fight occurred would now form a very unimportant obstacle, even at the highest tides, especially to men fleeing before a victorious and bloodthirsty enemy. But an examination of the district shews that the river Sulby once occupied a much wider bed than is now the case, that it was a tidal estuary probably half a mile in width, and that its southern bank was at the very foot of Scacafel, where the enemy's flanking party was posted. To what extent the valley had already silted up in the 11th century it is impossible to say, but by comparing 16th century maps with those of the present day we may compute that, at the date of the battle, the river would probably be quarter of a mile wide at high tide, and would very effectually cut off any retreat in that direction.
Such changes result from the tendency of rivers to silt themselves up where river and tide meet, or where the flow is retarded by an obstacle. Thus the lake referred to above, on the Silverburn river, seems to have been held up by the lump of boulder clay on which the Castle is built. For, painful though it be, the truth must be told. Castle Rushen is not built upon a rock, except in so far as clay is geologically rock. At all events it is not built on the sort of rock referred to in the numerous sermons for which it has served as an illustration; but on an erratic mass, deposited in the river's course during the ice age. It is one of many similar deposits in the district, that on which Billown House stands being perhaps one of the most prominent. The particular lump or mass with which we are more immediately concerned seems to have found rest in the very fairway of the river, and to have thus dammed up and diverted it. When discovered by the builder of Castle Rushen, it was neatly rounded by the elements, and if not entirely surrounded by the river, was very nearly so. At all events it was almost surrounded by a wide ravine, very much wider than the narrow space which is now misnamed the moat. So we find that what now appears to be a very weak site was originally excellent. It consisted of a rounded hummock separated from the surrounding high ground by a ravine. Further landward there were lakes and marshes, narrowing the enemy's front and enabling the garrison if so disposed to seriously check his advance.
* Chronicon Manniae.