But few people know that Scotland was forced by economic necessity to sign that Act following a ruinous attempt to establish a trading colony at Darien in the inhospitable jungles of Panama. The decision to set up a Scottish colony in the tropics was driven by domestic economic crisis. At the end of the 17th Century, Scotland was weary after years of war and famine, its trade damaged by England's wars with Europe. William Paterson - founder of the Bank of England - foresaw that global trade from commodity-rich countries across the isthmus of Panama - the slender land bridge that separates the Atlantic and Pacific Oceans - would grant global economic dominance.

Facing English resistance, Paterson raised £400,000 - everyone from farmers, merchants and chambermaids invested in the scheme - and half of Scotland's liquidity flowed to the tropics. Five ships set sail in July 1698 with more than 1,000 passengers on board. But Paterson (right) had never visited Panama, and knew nothing of the region's extreme climate, rampant tropical disease and cruel geography. So the unready adventurers set off with pathos-heavy trinkets, mirrors and combs to trade with the indigenous local Kuna tribe. The Kuna weren't interested. Short of food (poignant letters home detail pleas for a "stone of cheese" and a "case of brandy"), suffering from tropical illnesses, drunken shipwrecks, fires and under constant attack by the Spanish, the few surviving settlers abandoned the colony just over a year after arriving.

However, word of this did not reach Scotland before a second expedition departed with more than 1,000 people aboard, arriving on St Andrew's Day in 1699. Of the total 2,500 settlers that set off, just a few hundred survived. The Scottish economy was ruined. Seven years later, the Scots were forced to beg help from the English. It came at a price - the signing of the Act of Union, effectively ending Scotland's independence. English meddling certainly played a role in the failure of the scheme, since Westminster and the Crown forbade any trade with the new outpost. But this gloriously mad tale of bewigged imperialist arrogance is a stark warning on the dangers of standing alone in a globalised world. It might even give the more strident voices calling for renewed Scottish independence pause for thought.