The 19th century was the Age of Nationalism in Germany and Italy, among the subject peoples of the Habsburg Empire, and in Ireland. But in Scotland there was no political nationalist movement. Cultural nationalism flourished; it was then that the cult of William Wallace, heroic leader in the late 13th-century War of Independence, took off. The Wallace Monument was built by public subscription to stand on Abbey Craig outside Stirling, overlooking the field where he had won the Battle of Stirling Bridge, and other statues were erected in Aberdeen and Edinburgh, where he guards the Castle gate with his heroic successor Robert the Bruce. But this was an expression of national or patriotic feeling comfortably contained within Kidd's "banal unionism".

 H. E. Marshall's history for young people, Scotland's Story, offers a full expression of the nationalism-within-unionism position: "The hatred between Scotland and England has long died out. The two countries are now united into one kingdom, under one king. And everyone knows that it is best for Scotland and best for England that it should be so. Wallace in his life did his very best to prevent that union. Yet both Englishmen and Scotsmen will ever remember him as a hero, for they know that, in preventing Edward from conquering Scotland, he did a great work for the empire to which we both belong. If Scotland had been joined to England in the days of Edward, it would have been as a conquered country, and the union could never have been true and friendly. When hundreds of years later the two countries did join, it was not because one conquered the other, but because each of the two free nations, living side by side, wished it."

The actual achievement of Union may have been a more murky business than Marshall allowed her young readers to suppose. Nevertheless, her argument was valid. Thanks to the Wars of Independence, Scotland's history was to be very different from Ireland's. So in the 19th century heyday of Empire there was no political nationalist movement in Scotland — or none of any significance. The Union was evidently beneficial. It seemed, as she wrote, "firm and unbreakable".

It no longer appears so. Scots are no longer partners in the Empire, for the Empire is no more. Meanwhile, the British State became increasingly centralised in the second half of the 20th century. Speaking in Edinburgh during the 1950 General Election, Churchill declared that he "would never accept the view that Scotland should be forced into the serfdom of socialism as a result of a vote in the House of Commons", an observation that sounds strangely like a denial of what the Scottish judge Lord Cooper called "the peculiarly English idea of parliamentary sovereignty". Be that as it may, Churchill's words were a perfect expression of Kidd's "nationalist unionism". Over the following decades, however, more and more Scots voted Labour (even if not for that "serfdom"), and it was the Tory governments of Margaret Thatcher which were held to have imposed centralising policies on Scotland, despite her party's declining electoral support there. Thatcherism, whether misrepresented and misunderstood or not, was resented in Scotland, and the experience of 18 years of Tory government gave the cause of devolution an irresistible impulse.