KELMIS, Belgium (Reuters) - A small town in Belgium that spent a century living outside the map of Europe’s great power system celebrates the 200th anniversary of the quirky autonomy it secured in the wake of the Napoleonic wars.

Performers take part in a re-enactment during festivities in Kelmis, Belgium, May 21, 2016. REUTERS/Eric Vidal

Neutral Moresnet was the name given to the sliver of land, barely a square mile, that was home to a key deposit of the zinc ore calamine. It inspired tourists and anarchists - and utopian enthusiasts for the world language Esperanto - before succumbing to another round of the European bloodshed that gave it birth.

Granted independence in 1816 to keep a peace between Dutch and Prussians following the defeat of its former French imperial masters at Waterloo, it was swept away 98 years later by World War One. Now, as a town called Kelmis, it sits in Belgium, in the small German-speaking region close to Aachen in Germany.

“This is a unique history. This neutrality was a one-off. It has historical significance and that’s a good reason to celebrate it,” Kelmis mayor Louis Goebbels told Reuters at the start of a weekend of festivities for the bicentenary.

These included parades by Napoleonic military reenactors and lectures on the prosperity and freedoms enjoyed by defenceless, tiny Moresnet amid a Europe held together ever more shakily by the balance of powers forged at the Congress of Vienna.

Claimed by war-weary Prussians and Dutch, the Aachen Borders Treaty of June 26, 1816 divided the district of Moresnet between Berlin and Amsterdam with a narrow triangular strip containing the mine itself under shared control as Neutral Moresnet. When Belgium seceded in 1830, it took over the Dutch interests there.

Run by the Vieille Montagne company, which boomed by cladding the roofs of Paris and other cities with rain-proof zinc, the population of the 3.4 sq.km. territory soared from 256 in 1816 to nearly 5,000 by the start of World War One in 1914.

PEACEFUL “ANARCHY”

Mayor Goebbels relates how his forefathers came from Germany to the “neutral zone”. The mine, aware of a celebrity status that came from running its own state, was a model employer, offering a host of welfare services and sponsoring social clubs.

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For some there was also the draw that residents of what is known in French as La Calamine could avoid military service in Prussia or Belgium. Low taxes, notably on home-brewed alcohol, drove a thriving liquor trade -- and much smuggling.

Law was largely dispensed locally with a light touch.

It is cited as a model by libertarians who liken it to self-governing communities of the Wild West: “Moresnet demonstrated the possibilities that statelessness holds out for peace, prosperity and good order,” U.S. financial trader and economist Peter C. Earle wrote in a 2014 study, “A Century of Anarchy”.

The limits of Moresnet’s independence, though, were obvious.

When in 1886 the company doctor, Wilhelm Molly, hit on the idea of the territory’s own postal service, with an eye to stamp collectors, the twin supervisory powers in Berlin and Brussels joined forces to stop him -- leaving just a few rare specimens.

As the mine declined, the ever enterprising Dr. Molly sought to make Neutral Moresnet a center for Esperanto, an artificial “world language” intended to promote peace. Renaming the neutral zone “Amikejo” -- Esperanto for a place of friendship -- Molly even commissioned its own national anthem in 1908.

But six years later, the breakdown of the “armed peace” that Europe had agreed at the Congress of Vienna a century earlier wiped Neutral Moresnet off the map. German troops swept it up and annexed it in their 1914 conquest of Belgium. After World War One, it was handed wholesale to Belgium along with other German-speaking borderlands as part of Berlin’s reparations.

A century and another devastating European war later, though dozens of stone border markers still dot the fields and woods, people in Kelmis find it hard to imagine their forebears carving out a space between great-power frontiers bristling with guns.

“After two world wars, people here don’t generally want to talk about the past,” said Sylvie Fabeck, curator of the local museum. Her grandmother was the last person born in “free” Moresnet, weeks before war broke out in 1914. “These events,” she said, “Are a chance to show what Neutral Moresnet was.”

It now lies in the 4-million-strong Meuse-Rhine Euroregion, an administrative area that embraces French-speaking Liege, German-speaking Eupen and Flemish Hasselt in Belgium, Charlemagne’s 8th-century capital at Aachen in Germany and Maastricht, the Dutch home of the European Union treaty.

Despite new checks on some of the EU’s unpoliced borders since last year’s migration crisis, the 11,000 multilingual people of Kelmis can now work easily in all three countries. As museum curator Fabeck puts it: “This is what is now Europe.”