I know it's going to sound dull, but I want to point out that last week was the 200th anniversary of the Louisiana Purchase.

You may never even have heard of this affair, but for some reason, when I was a boy at school, it was one of the very hottest of topics for history teachers - it fair transported mine into that strange, robotic mode that is bred in the bones of some of that ilk.

The signs were unmistakable. He would settle one haunch on the edge of the desk, look up to gaze at a distant spot visible only to himself, and launch off into several hours-worth of droning on and on and on, to be followed by the assignment of more hours-worth of homework and, when the topic was eventually exhausted, weeks later, dire warnings about the certainty of an exam question. Made you feel like borrowing Lizzie Borden's axe.

But freed from the stupefying grip of a boring history teacher, it turns out that the Louisiana Purchase was quite an interesting event.

For a start, the name understates the case a bit. What was then called Louisiana involved not only what is now the state of Louisiana, but also the most of the land that later became the states of Arkansas, Missouri, Iowa, North Dakota, Texas, South Dakota, New Mexico, Nebraska, Kansas, Wyoming, Minnesota, Oklahoma, Colorado and Montana.

If you look at it on a map, that chunk of land is the entire midsection of the United States. It splits the country into three north-south chunks, forming a vaguely wedge-shaped mass in the middle that runs from the border with Canada in the north all the way down to the Gulf of Mexico, from the Rocky Mountains in the west all the way over to the Mississippi river.

That most cunning of creatures, Emperor Napoleon Bonaparte, got hold of this wedge from Spain (that's another story), and was going to use it in two ways. From a practical standpoint, it allowed him to supply French colonies in the West Indies with food and other supplies from near at hand. It also had a strategic use, in the sense that it could be an impenetrable barrier to any westward expansion of the young United States. Needless to say, it could also have made a nice chunk of a start-up empire on this side of the world.

Unfortunately, he ran into problems. First of all, he was just about to launch himself into a war with Britain that he was anxious to win. Second, 12 years of warring with a gang of mutinous slaves in Saint Domingue (known now as Haiti) had ended badly, and his troops had been pushed off the island. Napoleon needed money badly.

So first, he cut his losses in Saint Domingue. Then, he put feelers out to see if the US wanted to use the port of New Orleans and the Mississippi river badly enough to put some money on the table.

"I shall not keep," he is supposed to have said to one of his ministers, "a possession which will not be safe in our hands, which will perhaps be the cause of a clash with the Americans, or perhaps make them cold towards me. On the contrary, I shall use it to bind them to me, to cause them to break with the British, and I shall create enemies against the latter who shall one day avenge us." Doesn't sound much like him to me, but it's a pretty sort of allegation.

The then US president, Thomas Jefferson, asked the American minister to France, Robert Livingston, to go and talk to Napoleon. He sent his political prot?g?, the American statesman James Monroe, to France to help.

But instead of wanting to sell them just the port of New Orleans, Napoleon made the surprising suggestion that they should buy the whole Louisiana shebang. He wanted $22.5 million. They settled at $15 million, which works out at something like four cents an acre for 800,000 square miles of land. It was certainly the biggest real estate deal in history, and it's hard not to think that Napoleon got himself hosed down a bit... especially given the fact that he lost the war with Britain as well.

So what's with this bargain-basement land deal, I hear you ask.

Start with music.

Before the Louisiana Purchase, the biggest centre of influence in the young United States was New England.

There, the music was largely white and European and a little. well, let's call it a little lowbrow, only because a better term doesn't leap to the tongue. The music of those days in that place was largely Irish and Scottish, with their jigs and their reels.

In 1800, the year Haydn's 'The Seasons' was given its premiere in Europe, and Beethoven began publishing string quartets, Americans were exposed to church music and not a lot more. besides the jigs and reels, that is.

The first time European classical music got any kind of serious attention in the United States was 1815, when the Handel and Haydn Society was started in Boston. Half a century later, American audiences were said still to have the habit of interrupting performances of Mozart, say, to demand the band play Yankee Doodle, or something of that sort.

But after the Louisiana purchase, there was New Orleans. And who can think of anything that had a greater influence on music in America than the port of New Orleans? What a witches' brew of influences gathered in that place in the early days of the United States! The ability to move goods by water up the Mississippi into middle America made New Orleans one of the principal ports of the new nation.

Just to talk about major influences, there were the French of course, the Spanish too, but also the most amazing ingredients coming up from the Caribbean and South America.

New Orleans was the centre of the Caribbean/American slave trade. African slaves from the West Indies regularly practised and performed their music and dance rituals in what was then known as Place Congo, now Congo Square. People who learned about Congo Square's performances came from all over the countryside nearby to listen and watch.

Free Creoles built a substantial community in New Orleans, acquiring wealth and property. It was they who gave New Orleans much of its look, building churches and houses and throwing in that wonderful ironwork for balconies and doorways. French opera flourished among the Creoles, black marching bands performed in the streets, and musicians of all kinds found work in dancehalls and saloons in the new, swingin' Louisiana.

New Orleans' taste for music became famous, and other types of musicians were drawn to the City. French Acadians, expelled from Canada, fled there with their accordions, and became known as Cajuns. Fiddlers and banjo pickers from all over the United States went there to work, and native Indians with their complex chants also had an influence.

The United States' first great composer, Louis Moreau Gottschalk, came from New Orleans.

He was a Creole, born in 1829, who was heavily influenced by French music, and by the Caribbean folk-music of some of his ancestors. As a boy, he liked to dance to the music played in Congo Square, and often did until he dropped and had to be carried home.

Gottschalk studied piano in Paris, and travelled extensively through the Caribbean and in South America all his life. He died, in fact, in Brazil, in Tijuca, which is now a part of Rio de Janeiro. He was famous throughout Europe for his exotic music, which is to the ear what a dish of luscious plums, dusted with sugar, is to the eye. If you're interested, 'Google' him.

If Gottschalk was the first fruit of the New Orleans tree, there were lots more to come, each one giving rise to the next. I don't think you can claim the blues or spirituals or minstrelsy were born in New Orleans, but they were all certainly a part of the mix that gave birth, in that city, to something that carried echoes of it all, something completely and utterly trans-American, as American as a Tommy-gun in a violin case.

Buddy Bolden is generally considered to be the first bandleader to play the improvised music that became known as jazz. Bolden was the first "king of the cornet" in New Orleans, and was known among musicians of that time for his loud, clear tone.

His band starting playing around 1895, and became one of the most popular in the city. His roots were not so much in the brass bands that played on the street, as they were in the string bands that played for hire in rather more genteel settings.

Bolden's rise to fame coincided with the emergence of a black pleasure district, Storyville, at South Rampart and Perdido streets, where he became a local celebrity, playing in its dives and honkytonks.

A young Louis Armstrong listened to him there, as did dozens of other young musicians who would carry forward and develop his improvisations.

In 1907, he had a sudden mental seizure of some kind. He was committed to a mental institution, where he spent the 25 years that remained of his life. He made no recordings during his career (there is supposed to have been a player piano roll of some kind, but it has never been found). However, several early musicians like Sidney Bechet and Bunk Johnson were said to have played in his band and later played in his style.

Bolden's theme tune was called Funky Butt, and the present-day jazz standard, "Buddy Bolden's Blues (I Thought I Heard Buddy Bolden Say)" is said to have been based on it.

From Buddy Bolden. it's as if a magic carpet of wonderful musicians and their extraordinary music rolled out of New Orleans, grew and spread to every corner of the globe. There can't be anyone on the planet whose life hasn't been touched by the result of that New Orleans brew.

So what's with the land deal is this: I think it's worth remembering that, in a way, it's all down to that funny little French genius of generals, Napoleon Bonaparte, who wanted to defeat Britain and be a friend to the United States.

I think it's worth reflecting that if he knew what that pair, M Chirac and M Villepin, had done in the last few months to drive the United States and his old arch-enemy, Britain, into each other's arms. well, I suspect the guillotine might have been given a little curtain call, and there'd have been jigs and reels for after.