Firmly nailed to the mast of this year’s referendum on Scottish independence, Linda Colley’s three-week-long series (from 6 January) is, as one might have predicted, an attempt to de-mythologise vast stretches of recent British history. Not that Professor Colley would have had much truck with a phrase like “vast stretches of recent British history”. Much of the opening instalment of Acts of Union and Disunion, in fact, was concerned to emphasise quite how little “British” history actually existed and how thoroughly artificial the idea of “Britain” was when set in any kind of long-term context.As ever, it was instructive to be reminded that one’s first identifiable ancestors are no more than 11,500 years old; that America and Australia