T

here are two Graham Robbs. One writes scholarly biographies of French literary giants and cleverly idiosyncratic French histories — notably The Discovery of France, which I loved when it came out almost 20 years ago.

The other Robb swaps the mortarboard for a tin foil hat. In 2013 he offered “evidence” of what I can only bring myself to call Celtic ley lines. In 2018 he claimed to have reconstructed a map of Celtic Britain which proved, among other things, that King Arthur was real.

In this remarkable account of Britain — from Iron Age hut-dwellers to paedophile priests — you get both Learned Robb and Mad Robb. The good news is that the former writes as beautifully and intelligently as ever. The Discovery of Britain is less a grand narrative than a sequence of historical essays. Robb plucks curious details from history and sets them against anecdotes from his bicycle-powered researches on the ground, and childhood memories.

Robb is obsessed with the way the past brushes up against the present. Describing the earliest houses in Britain, from about 3,700BC — about 81 lifetimes ago — he observes that they were “slightly more spacious than the average detached house”. That brings the ancestors close. Then he adds that some of those earliest homes had adjoining rooms for the dead. That distances them, rather.