How – and why – did the crusaders rise and fall? As Malcolm Barber writes in this lively history of what followed the capture of Jerusalem in 1099:

to the modern eye, the crusader states may appear no more than narrow strips of territory clinging to the coast on the farthest fringe of Christendom, but to contemporaries they were the guardians of the holiest shrines at the very heart of the Christian world.

Barber tells the story of the Crusades from the perspective of the Holy Land itself, above all from the kingdom of Jerusalem, but also from the other Christian principalities and counties that emerged at the end of the 11th century. He draws on an extraordinary collection of Western sources that drip with detail, gossip and the settling of scores. Barber is a highly distinguished scholar, whose touch is continually deft, and he navigates the biases of the main narrative histories with care, never prepared to take allegations and accusations at face value. The result is both genuinely illuminating and highly enjoyable.

As Barber makes clear, the crusader states were volatile and unpredictable. Things had to be made up on the hoof (laws, taxes, land grants, concessions), which proved highly problematic,