What has the union done for us cry the Nationalists rather like those characters in the Life of Brian wondering what the Romans have ever done for us. To ask the question is to answer it.
The trouble with most nationalists is that they actually appear to know very little about Scottish history or literature. Anyone who compares and contrasts Scotland prior to the union with Scotland after the union will immediately see exactly what the union has done for us.
A quick glance at Scottish history pre union shows an obscure European country, much poorer than the average, fighting continually with its larger neighbour or alternatively fighting with itself. One of the most dangerous jobs in Scotland was to be king and the most notable feature of most reigns was treachery, factionalism and assassination.
There were, of course, some wonderful things which developed in Scotland, pre-eminently the four ancient universities. There are some fine thinkers and writers. Dun Scotus is one of the greatest of medieval philosophers. John Barbour's Brus is still studied in universities as is Blind Harry's Wallace. The people they wrote about Robert the Bruce and William Wallace are celebrated as heroes the world over as is Mary Stuart, but there's little else in pre union Scottish history or culture that has travelled beyond this country. From the perspective of the rest of the world, pre union Scotland amounts to Braveheart and Mary Queen of Scots ruling romantically, shambolically and in the end tragically.
The union of the crowns in 1603 immediately brought cultural and linguistic benefits. King James VI a Scottish King on the throne of England made one of the greatest contributions to the English speaking world by publishing the King James Bible and he published it not in his native Scots, but in English. Precisely for this reason English gradually took over in Scotland bringing us one of our greatest benefits from the union, a language spoken the world over.
Up until the union people in Scotland spoke and wrote either Gaelic or Scots, the latter a divergent strain of Anglo Saxon rapidly developing into a language which would no longer be mutually comprehensible with English. If Scotland had remained independent, the likelihood is that we would now speak a language in Scotland as different from English as Dutch is from German. But instead with the introduction of the King James Bible and the prestige of the court in London, English came to be the dominant language in Scotland, leaving Scots as a language spoken on the margins less and less used by the educated, used in literature, but mainly as dialogue, poetry and song, barely used at all in philosophy or economics or history or in the church. We may regret this, but the benefits to Scotland today of speaking a world language are obvious and it can be traced to the union of the crowns.
With the union of 1707 came further benefits. Scottish merchants, now protected by the Royal Navy and with new markets opened up to them, which had been closed before, were able to begin to prosper as never before. Prior to entering into currency union with England in 1707, 12 pounds Scots obtained 1 pound Sterling. The Scottish economy was bankrupt after the Darien scheme, but rapidly the union brought prosperity, the benefits of a strong stable currency, order and increased trade, both within the union and without.
As in England, Scotland had been fighting a civil war since the 1630s, which amounted to a fight between Presbyterians on one side versus Catholics and Episcopalians on the other. This same civil war continued, on and off, throughout the reigns of Charles II, James II and VII and had its final battles in the attempts to restore Stuart rule during the Jacobite rebellions.
Many Scots, including me, love the romanticism and the fundamental justness of the Jacobite cause. But thinking Scots realise, that only with the final defeat of the Stuarts and with it the doctrine of the divine right of Kings, arrived the Scottish enlightenment and the prosperity that followed. Bonnie Prince Charlie nearly won in 1745 and without the union he may well have done so. My heart wishes that he had won, but my head realises that Scotland prospered with the Hanoverians, that parliamentary democracy and the idea of constitutional monarchy brought in with the "Glorious revolution" of 1688 was the key to us avoiding the horrors of revolution which engulfed France, the French domination which Jacobite victory would have brought, and so while I toast the king o'er the water, I am glad he remained there.
The end of the century long British Civil war in 1745, brought stability, boredom and prosperity, with it came Scotland's greatest period of intellectual and cultural development. What did the union ever do for us? For one thing, it gave us David Hume (1711-1776), considered by most to be Britain's greatest philosopher and studied the world over wherever philosophy is taught. The union, without which the Scottish enlightenment would not have happened, gave us Adam Smith (1723-1790), perhaps the world's greatest economist. The wealth, which the union brought enabled architect Robert Adam (1728-1792) to design and build, many of the buildings which we most associate with the architectural style of Scotland. Henry Raeburn (1756-1823) painted the Scots who were prospering from the union. Scotland's greatest poet Robert Burns (1759-1796) considered himself a unionist Scottish and British and because he used the Scots language to address concerns which touched the hearts of everyone, rather than addressing narrowly nationalistic issues, he carried that language the world over, giving the world a song sung everywhere on the 31st of December.
Scotland's greatest novelist, Walter Scott (1771-1832), perhaps did even more than Burns to promote Scotland and virtually invented much of what we consider today to be Scottish culture. Scott who was wildly popular the world over, virtually invented the historical novel and influenced each historical novelist who came after from Victor Hugo to Lev Tolstoy. His novels helped to heal the wounds of the Jacobite rebellion, because Scott himself was a Jacobite with his heart, a Hanoverian with his head. It is this duality which makes his novels complex and interesting. He wrote about Scotland in a way that made the English love Scotland and because he was a unionist he loved them back, sparking the revival of interest in medieval England with his novel Ivanhoe.
It is unnecessary to continue much further the list of great Scots who flourished by being in the union. Britain's greatest writer of adventure stories Robert Louis Stevenson (1850-1894), and Britain's greatest writer of detective stories Arthur Conan Doyle (1859-1930), were hardly hindered by being from the UK. There are Scots inventors, like John Logie Baird (1888-1946), Alexander Graham Bell (1847-1922), scientists like Alexander Fleming (1881-1955) and James Clerk Maxwell (1831-1879), famous the world over. What do they have in common? They were all unionists.
It's almost impossible to find a major writer or thinker prior to the 20th century who seriously supported independence. In fact, the only major writer I can think of who the SNP can claim is Hugh MacDiarmid (1892-1978). He was an important and fine writer, but notorious for his hatred of the English, listing Anglophobia amongst his hobbies in his Who's who entry.
Nationalists therefore reject the point of view of nearly all those who made Scotland great and do so in a language they would not even be able to speak without the union. They romanticise an independent Scotland through figures like William Wallace, who we only know about through myth, poetry and Hollywood lies and nonsense. They want to resurrect a country, which was obscure, poor and violent and reject a country which gave us the world and made us world famous: shame on them for their narrow nationalism and lack of patriotism.