London in 1215 was already an independent-minded place; large, rich, well-connected and hard to rule. It was the largest city north of the Alps, with nearly 15,000 residents*, and its power was growing. At the same time King John's disastrous reign was falling apart. His armies were retreating in France, he was running out of money and his Barons were on the edge of open revolt.
The city of London, squeezed by the King's taxes and frequently held hostage in baronial disputes, had been trying since the late 1100s to organise itself into a mediæval commune. The King may have thought he was creating a powerful new ally** when in 1215 he gave his support to the commune and issued a Royal Charter allowing the City to elect its own Mayor every year.
There was an important condition. Every year the newly elected Mayor must leave the safety of the City, travel upriver to the small town of Westminster and swear loyalty to the Crown. The Lord Mayor has now made that journey for over 800 years, despite plagues and fires and countless wars, and pledged his (and her) loyalty to 34 kings and queens of England.
In fact the loyalty of 13th century London was quite flexible, and it was the city's support for the rebellious barons that finally brought the King to the negotiating table. Two months later the second elected Mayor, William Hardel, was one of the 25 signatories to the Magna Carta and no doubt responsible for the inclusion of part 13:
13. The city of London shall enjoy all its ancient liberties and free customs, both by land and by water. We also will and grant that all other cities, boroughs, towns, and ports shall enjoy all their liberties and free customs.
The Mayor of London became the Lord Mayor about a century later and for the next few hundred years, Lord Mayor of London was by far the grandest position to which a commoner could aspire. The Mayor's journey was the celebrity spectacle of its day and over the centuries it grew so splendid and so popular that by the 16th century it was known everywhere as the Lord Mayor's Show. It features in the plays of Shakespeare, the diaries of Pepys and the adventures of James Bond and of course in the pantomime story of Dick Whittington, who really was the Mayor of London three times. In the 20th century the Lord Mayor's Show was the first outside event ever to be broadcast live and it still attracts a TV audience of millions.
The modern Lord Mayor's procession is a direct descendant of that first journey to Westminster. The route and date have changed over the years but the pageantry of Hogarth and Canaletto can still be seen in its lively mixture of London's past, present and future. The state coach is over 250 years old, and the pikemen who guard it are almost as old as the Show. Today you will see the City's businesses, Livery Companies, charities, Her Majesty's Forces, the City Police and Londoners from all walks of life come together to enjoy a splendid celebration of the City's ancient power and prosperity, just as they did in the middle ages.
* Not a very big city by modern standards, but still that's twice the resident population of the City of London in 2011.
** If so, the King's plan didn't work very well. Less than a year later, after both sides had ignored the terms of the Magna Carta, the struggle between John and his northern barons became a civil war. Robert FitzWalter, leader of the rebel alliance, had based himself in London. After a series of silly blunders he was forced to seek help from France. We are told that Londoners lined the streets to welcome the invading Prince Louis and his troops.