To The Ends Of The Earth: Scotland's Global Diaspora, By Tom Devine

Two hundred years ago, on 28 August 1811, the Rev Dr John Leyden, lawyer, soldier, folklorist, poet, linguist extraordinaire, died at Batavia (Jakarta) – of a chill contracted in the Dutch archives he had, with his laird Governor-General Lord Minto, just captured. "A distant and a deadly shore/ Holds LEYDEN's cold remains," mourned his friend Walter Scott, about to publish Waverley, the greatest of all historical novels - whose influence on imperialism Professor Devine presciently acknowledges.

Leyden doesn't appear in Tom Devine's book but somehow typifies it. The idea-image of a "diaspora" – originally a Jewish coinage – that implies gain as well as loss seems to fit a Scots story ranging from deserted sheilings to Andrew Carnegie's millions and the 1917 Balfour Declaration, which reversed the Diaspora. This multivalence is never entirely cleared up, but the book fascinates.

Devine excels in demographic and economic themes, reflecting two classic books with a Scots-imperial hinterland: JA Hobson's Imperialism, written in an early Scots settlement, Manchester; and George Orwell's Nineteen Eighty-Four: written on Jura with a language, Gaelic, dying around him. Both are about the commodification of people, by capitalists or communists, and the unstable "surplus value" this creates.

Here Devine extends himself to manufacture, which figured only briefly in his Scotland's Empire. His key chapters – on slavery, technics and investment, and migration – are magisterial, particularly when compared to Niall Ferguson waffling about "Killer Apps" in Civilisation.

The idea of "diaspora" complicates rather than simplifies, particularly given Devine's conclusion that migration meant people becoming elastic rather than exiled. "Returners" were important, living feedback-loops, or like poor Leyden, vivid tabulators and reporters. Women had to manage much of this, and Devine (like the rest of us males) could do better. There is good stuff on their preponderant role in missionary work, but barely 20 index entries.

Devine is limited on literature and the "new church" of journalism, though they supplied the elastic. Thomas Carlyle produced that phrase, and it was the Americans who really discovered him. Other non-appearers: Rupert Murdoch, whose grandfather set out in 1886 to foster the Australian Free Kirk; prototype "Mad Man" David Ogilvie; the eminently sane JK Galbraith. Plenty of names are cited, but are there enough of the "ologies" that fired up the Leydens and produced useful synergies of cash and engineering with horticulture, stockbreeding and so on? In the 1870s, the New Zealand Scots combined the steam engine, the refrigerator and the clipper to start the chilled meat trade.

On the military dimension, Devine shrewdly interrogates the reputations. In and out of uniform, the Scots lived with a homeland whose low wages and poor housing propelled them abroad; while exported profit captured the land, and grew the trade, that enabled them to thrive. In 1861-71, other peoples' wars - in Europe and America - coincided with the Scots' great moment of iron, cables, and steam. They stretched it to 50 years. In the new lands, the English upper class replicated cathedral close, quarter-sessions and country estate; the Scots had the machine shop, technical college and public library.

The most recent diaspora has been that of the "offshoremen". They are now to be found wherever oil can be (increasingly riskily) pumped out of the deep, but return to a near-deindustrialised country. Devine explains why, ending intriguingly on the boom in Scots-American heritage. The Alex Salmond SNP government in Edinburgh has staked a lot on "homecoming", though you reach the Catalan-designed Holyrood parliament down a bizarre Royal Mile of tartan-tat shops run by engaging Sikhs with accents broader than the Forth, who would certainly have held their own on Kipling's Grand Trunk Road.

Scots deployed synoptic ideas on efficiency and economy, but also in simple, sensible things like Sanford Fleming's time zones and the marvel of MacMillan and Dunlop's safety bicycle. Did the relentless US nemesis begin in Vietnam, where its hi-tech billions faced "these little guys pushing bikes who just kept on coming, moving thousands of tons", as a US strategist put it after the defeat?

The last Scots shipyards are building two aircraft-carriers commissioned by Gordon Brown, supported by the Scots-Irish Tory Liam Fox, and indeed by Salmond. The previous "Prince of Wales" was sunk off Malaya in 1942 by Japanese bombers. Their builder and its founder? Mitsubishi and Thomas Glover of Fraserburgh: another of Devine's men.

Christopher Harvie's most recent book is 'Broonland' (Verso)