The word ‘magisterial’ consistently attaches itself to the work of David Kynaston. His eye-wateringly exhaustive four-volume history of the Old Lady of Threadneedle Street established him as a historian with a confident command of a huge body of information, as bloodless and dry as the subject was. Embarking on Tales of a New Jerusalem, a history of Britain from 1945 to 1979, he has undertaken another marathon and earned magisterial rank.