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I'm sure it is possible to have a Britain that is never conquered by Rome... After all, Hibernia and Caledonia were never incorporated.

How would Britain develop in this scenario? Compared to OTL Ireland, I suppose Britain would develop at a slightly faster pace than Hibernia due to closer contact with the mainland. Development over all, however, would likely be slower. The Britons would remain organized into tribal kingdoms, with a ceremonial High King on top and various levels of sub-kingdoms below... With the Angles, Saxons, and Jutes out of the way, Britain might maintain a bastion of civilization in the Dark Ages. Roman intellectuals and Christian missionaries would flock there, slowly converting the natives. Eventually Viking incursions might call for a stronger, more centralized form of government.
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