After the defeat of Harold II in 1066 following the Norman invasion, the Doomsday Survey of 1086 was an attempt by William the Conqueror to list all the taxable land in his new kingdom, to identify who owned what and how many men he could call on for military service. Most of Cumbria was in possession of the Scots, except for the Furness and Cartmel peninsulas and areas around the Duddon. Furness was therefore at the far flung corner of his kingdom.

The Doomsday survey is the earliest record we have of land holdings in Furness. Most of the vills were listed as having belonged to Earl Tostig (Harold's wayward half-brother) before the Conquest, as part of the manor of Hougun (left below and marked as green and yellow on the map below). The size of each holding was marked in carucates (an area of land roughly equal to 0.5 sq. km). However, some holdings (including Ulverston or Ulvrestun) were listed with Kendal as part of Yorkshire (right below and marked in pink on the map).

Unfortunately, not all the names used can be related to present day place names and over the years there has been much discussion about some of the more obscure areas (marked in yellow on the map).

Two of the vills that have proved difficult to identify, but which are of most interest here, are Borch (6 carucates) and Suntun (two carucates).

When the known vills (green) are marked on a Furness map according to their approximate size in carucates (although the actual land holding would have been much more irregular), we see that they were not listed at random but in some order; the gaps and the order allow one to make logical suggestions about those “missing” vills. This is my interpretation of Doomsday – many others are available.

Thus, every vill fits logically into place (earlier attempts to identify the vills seem to have overlooked this numerical evidence). It should be remembered that the scribes compiling the list of taxable holdings for William probably never visited this remote corner (hence Ulverston being listed with Yorkshire) and merely recorded what they were told, sometimes guessing at the spelling. It is my belief that Borch (the “ch” was pronounced “k”, as in cherche meaning kirk or church) represented the area between Ulverston and Birkrigg (see below), including Skelmore Heads (an area clearly important in pre-historic times, as we have seen). Borch is perhaps a corruption or misspelling of the Old English beorc and Old Norse birk meaning birch. That would make Birkrigg "the ridge on the edge of an area called Birk or Borch" rather than a "ridge covered in birch".

Suntun may be the area between Bardsea and Aldingham, roughly present day Sunbrick-Baycliffe. Opinions differ as to whether the first part of the name Sunbrick derives from the Norse svein meaning pig or sun (Sunna was the Norse godess of the sun). Personally I prefer the latter, as “sun slope” is a very apt name for these sheltered fields with fertile soil, and the placing of the Sunbrick stone rings in this area is clearly linked to sun rises (svein makes much more sense for Swinside).