The Shield Ring and The Secret Valley

[hedgebird]

I've read more than once that Rosemary Sutcliff's Anglo-Norse vs. Anglo-Normans novel The Shield Ring was founded on a book called The Secret Valley by one Nicholas Size. The Wikipedia page for Buttermere, for example, which calls it a "dramatized history," mentions their connection. Elsewhere his book is called a novel and this puzzled me a bit, as in this essay Sutcliff described her inspiration for The Shield Ring as "a little privately published handbook" – i.e. a work of non-fiction. Detective Me concluded she might really have meant Size's earlier treatment of the material, a little booklet mentioned on his Wikipedia page.

Of course this slight discrepancy might be moot if I could read Size's books, but I've never found a copy online (for free; there are limits to curiosity.) But now I have found a relevant excerpt from The Secret Valley in an anthology! "The Battle of Rannardale" covers the entire timeframe and alleged historical background of The Shield Ring. It's in My Favourite Stories of Lakeland edited by Melvyn Bragg (the radio host) and you can read it on Internet Archive.

But in case your curiosity on this point does not extend quite that far, I have extracted four bits that will sound familiar to readers of The Shield Ring. Casual readers like myself, that is; textual experts might well find more amid Size's welter of geographic details that Sutcliff could have cribbed. Non-readers will find these very vaguely spoilery.

• "Everybody knew that sooner or later the valley would be attacked from the North, but the novel defense which the Earl had been perfecting for years gave them confidence... This defense which pleased them so much was nothing less than the diversion of the road or track from over the shoulder of Rannardale Knotts, near the lake, to a narrow and dangerous valley close at hand, where everything was prepared for a great killing."
• "Here sat Earl Boethar with his son Gille, and his trusty brother Ackin watching the approach of the Norman army." (Sutcliff calls these characters Buthar, Gille, and Aikin in The Shield Ring. Boethar/Buthar at least is a local legend, but the internet hasn't informed me whether Size invented his brother and son. Ranulf Meschin is another familiar name, but it's because he definitely historically existed.)
• "Such a thing was, however, only likely to happen if some traitor had betrayed the preparations, and none of the poor souls the Normans captured would be likely to say a word even under torture." (Embryonic Bjorn?)
• "[T]he archers on the ridge were reinforced by women". (Zygotic Frytha?)

I'm still not sure which of Size's books Rosemary Sutcliff read, the novel or the little booklet. But I can certainly believe that one way or another Size's work was the basis for The Shield Ring.