It was the small people who made the tactical difference at Bannockburn, but only because an approaching gaggle of camp-followers and other opportunists were mistaken for reinforcements by the English troops.

It is Chris Bambery's premise that the small people counted for little in early Scottish history and have only slowly risen out of obscurity to help shape - for good or ill - the country that now stands poised to decide its political future.

This approach doesn't preclude some good narrative history and Bambery's single-chapter account of how Scotland emerges, basically from the beginnings of documented history to the Wars of Independence, is as good a summary narrative as you'll find. What follows is more complex, given that it is driven by a desire to find in Scotland and in Scottish historiography models for a country predisposed to social justice but held back by 407 years of British (which is carefully distinguished from English) rule. In doing this, Bambery relies as heavily on poetry and song, and on figures outside the usual dynastic timelines and top-down frames of reference. Key to his account are potted biographies of figures as diverse as Robert Burns and Hugh MacDiarmid (the latter not quite pinned down), Red Clydesider John Maclean and Helen Crawfurd, the suffragist and rent striker whose name may well be unknown to readers who don't identify with the left: a powerful woman and a powerful story notwithstanding.

In locating much of his evidence in vernacular and polite culture, Bambery makes the important, if mainly tacit, point that the 2014 referendum isn't simply a question about how Scotland is to be governed in future but what kind of country it perceives itself to be. In doing this, he looks carefully at how religious sectarianism has intersected with economic and political tensions and how quite specific social ideologies have shaped voting decisions. He doesn't perhaps bring this quite up to date with a sense of how Scottish Catholics have gained a more distinct and confident social identity in recent years, nor how patterns of immigration to Scotland - by Italians, Poles, South Asians - have affected Scottish life and culture in ways that make "traditional" nationalism seem quaintly irrelevant.

Perhaps the most tiresome aspect of A People's History Of Scotland is its relentless populism and somewhat casual acceptance of the belief most forcefully expressed by Thomas Johnston, who described the Scottish nobility as "a selfish, ferocious, famishing, unprincipled set of hyenas, from whom at no time, and in no way, has the country derived any benefit whatsoever".

Johnston, who is first described as a "19th-century historian" and not identified until later as Scotland's most charismatic Secretary of State, returned to this theme often, most notably in Our Scots Noble Families ("our Old Nobility is not noble") but Bambery tends to confuse Johnstonian rhetoric with historical accuracy and to mistake a useful us-and-them heuristic with a genuinely realistic sense of how the Scottish aristocracy served, or failed to serve, the nation. He is consistently aware that much of what passes for nascent democracy in early Scottish history is actually self-service, a system maintained by the nobility to match its own ends, but then uses that as a rod to beat the landed classes up and down the corridors of time. To pass over the complicity of someone like Johnston in a polity that depended as much on the aristocracy as on collected votes, is more than a bit naïve.

In the same way, the book's knee-jerk anti-Thatcherism is precisely that, a galvanic and not entirely considered response that fails to examine the division between one-nation Toryism and the neo-conservatism served up, but by no means invented, by a second-rate scientist from Grantham. Thatcher used Scotland as her hostess trolley and Scotland has been politically the poorer ever since, not least because all decent liberal-left rhetoric since her time seems to require a round condemnation of her doings, indeed, of her very existence. Which misses the point, ever more obvious to those with eyes to see it, that arguably the biggest betrayal of the "Thatcher years" (which demands the scare quotes because they were no such thing) was the betrayal of a decent and responsible country interest and a "natural" order in Scottish politics defined by intelligent liberalism and balanced at the other end of the spectrum by an essentially Marxist Labour Party. (It's quite interesting that the name Grimond doesn't appear in Bambery's index.)

All the same, it's a good book, by and large, and a very readable one, but probably best considered as a timely intervention rather than a permanent contribution to historiography. My instinct is that by mid-October its many virtues will seem blunted and its undoubted passion inadequate to either outcome. This is pamphleteering of an attractively old-fashioned sort, but on an ambitious scale. It's a dying art and we should welcome it. It's to be hoped that Bambery's steady insistence on social justice as a higher political end, above party or nationalism, remains audible.