The wavy-bladed sword from Brisbane that links Filipino pirates to Lord Nelson

Archaeologist Adam Brumm usually deals with ancient artefacts — think million-year-old stone tools carefully chipped into shape by a human ancestor, or faded ochre paintings daubed on walls deep inside labyrinthine limestone caves.

But his current obsession is a relic forged just a few hundred years ago. It's a sword about as long as his arm, elaborately carved with animal likenesses and religious symbols, with a broad, wavy blade shaped like a long, flickering flame.

"I remember my brother saw it and he goes, 'my god. The bad guys in GI Joe, it looks like one of the weapons they would use, or an orc from Lord of the Rings,'" Adam says.

Yet it's not the sword's undulating blade nor its exquisite carvings that has Adam excited. It's what's written in faded ink on a scrap of paper stuck on the sword's sheath.

In cursive lettering, the label says the weapon is:

… a present from the [illegible] of Timor to Admiral Lord Nelson.

If Nelson — Britain's greatest naval hero — did once own the sword, the weapon would be an incredibly rare and valuable historical artefact.

Even if not, the sword's history tells a story of adventure and (attempted) colonial rule.

Adam bought the sword a couple of years ago from a collector who'd picked it up at a Brisbane gun show around the late 1980s.

Before that, the sword may have been wielded by fierce maritime raiders who laid waste to Spanish galleons for three centuries, helped spur the development of an iconic American pistol, and hitched a ride on the ship that completed the first circumnavigation of mainland Australia.

'Vikings of island South-East Asia'

Adam's wavy-bladed sword is a longer, heftier example of a traditional Indonesian weapon called a kris.

Kris are usually dagger-sized with pointy blades, but they're often considered spiritual or ceremonial objects rather than weapons.

They can be made from metal, wood, ivory and gold, and crafted by artisan blacksmiths. Different ethnic groups have different styles of kris.

Iwan Sumantri, an archaeologist at the Sulawesi Archaeological Research Collaboration Centre, has three or four kris in the style of the Bugis and Makassar people of South Sulawesi.

And each kris is revered — almost like a member of the family.

"Kris are like a wife, or a second wife," he says with a laugh.

Iwan was given his first kris when he was 15 years old. Now, six decades later, he still has it, and eventually will pass it and the rest of his kris on to his daughters and nephew.

But where Iwan's kris daggers are honoured heirlooms, Adam's much larger kris sword was made for killing.

It's a weapon typical of the Moro people: predominantly Muslim indigenous ethnic groups from the southern Philippines, Adam says.

"And in historical times, they were notoriously feared, formidable pirates and maritime raiders.

Their targets were the Spanish who, after colonising and Catholicising the Philippines in the 1500s, tried to subjugate Muslim Moro territory to their rule.

But the Moro people fought back. Fiercely.

"They were known to descend on lone Spanish galleons or Spanish-controlled coastal settlements in these huge fleets of fast-moving ships … and just lay waste to them," Adam says.

Moro hit-and-run tactics kept the Spanish at bay for centuries.

Spain eventually ceded the Philippines to the US at the turn of the 20th century, but not even gun-toting Americans sporting .38-calibre revolvers could bring Moro lands under their control.

"Up close, an individual Moro warrior … would just charge the American soldiers in the jungle with their kris and other weapons and killed a lot of them," Adam says.

"They were very, very difficult to defeat in close combat, so much so that it's said that the American army, after the experience of fighting the Moro with these kris, they developed a more powerful side-arm … because they needed a gun that could stop an enemy in their tracks.

"And so that was essentially the origin of the iconic .45-calibre pistol that revolutionised side-arm technology in the 20th century."

These days, after centuries of resistance and, more recently, several years of peace talks with the Philippine government, most Moro people mostly live in an autonomous region, on the island of Mindanao, called Bangsamoro.

A kris sword adorns the Bangsamoro flag.

Lord Nelson: Hero, celebrity, letter-writer

It's possible that the kris now belonging to Adam may have been brandished by a Moro raider who battled Spanish colonisers.

But if the label stuck to its sheath is to be believed, it was then presented to another seafaring fighter: Admiral Lord Horatio Nelson of the Royal Navy.

Nelson was, by all accounts, a brilliant tactician. He employed unconventional tactics to destroy enemy fleets and win seemingly unwinnable battles, most famously during the French Revolutionary and Napoleonic Wars.

During his career he lost partial sight in one eye, and was shot in his right arm, which had to be amputated.

He met his end at age 47 when he was shot by a French sniper during the Battle of Trafalgar in 1805. The Royal Navy won that battle, crushing Napoleon's plan to invade Britain, but Nelson did not survive.

His body was returned to England, and he's been recognised as a national hero since, according to Martyn Downer, who worked for Sotheby's in London and is an expert on Nelson and Nelson artefacts.

"So he's endlessly studied and endlessly written about, and objects and possessions that he touched are fought over by collectors."

Authentic Nelson relics fetch a pretty penny, regularly selling for hundreds of thousands of dollars.

One of Nelson's swords fetched more than 336,000 British pounds at Sotheby's in 2002. That was a little under a million Australian dollars at the time.

So is Adam's kris sword the real Nelson deal, and valuable, too?

When Martyn first heard about it, he was sceptical. The label on its sheath mentions Timor, and Nelson didn't go anywhere near that part of the world.

There's no mention of the distinctive sword in his collection, nor in the thousands of letters Nelson wrote over the years.

"It was such an extraordinary object to connect to a British officer of that date when contact with that part of the world and England was so scarce," Martyn says.

If someone wanted to pass off a fake as a genuine Nelson artefact, they might choose something he'd wear, like a naval hat or a medal — not an ornately carved wavy-bladed sword.

And when Martyn literally got a hold of the sword, he was convinced.

"The best way of working with an object is to actually handle it, because then the object itself can, to a degree, speak to you if you're familiar with handling objects," Martyn says.

"And this object … compellingly handles as something that is right."

The label, he adds, is also "very compelling". Its reference to "Lord Nelson" helps narrow down the time at which the kris may have been given. Nelson didn't become Lord Nelson until 1798 and he died in 1805.

It's not possible to read the name of the gift-giver, but they were in Timor. At that time, Timor belonged to the Dutch, and the Dutch were enemies of Britain, and weren't in the habit of exchanging gifts.

But they suspended hostilities in 1802 and 1803 during the Treaty of Amiens, so Martyn suspects it was probably offered as a present then.

"And it was a fearsome weapon … that was often employed by the pirates in the region, by high status members of the community, so if a weapon was going to be gifted to Nelson from that region, this is the weapon that it would be."

Well-travelled weapon

If the kris did make its way to Nelson's England home, the question remains: How did it get from Timor to England and then back to Australia, where it was eventually sold to a collector at a Brisbane gun show in the late 1980s or early 90s?

For the first leg of its journey, there is a chance it caught a lift with a well-known name in Australian colonial history (who happened to serve with Nelson in the navy): Matthew Flinders.

In 1802, Flinders and the HMS Investigator set sail north from Sydney to conduct the first circumnavigation of mainland Australia. While surveying the coastline of the Gulf of Carpentaria, Flinders discovered much of the ship was rotten, so he called into Timor looking for a replacement vessel.

Maybe, Martyn says, this is when Flinders picked up the kris, which later made its way to England with one of the Investigator crew.

There is, of course, the possibility that the kris never left the region, and instead was dropped off in Sydney by Flinders after circumnavigating the continent. But there's also a potential route from England to Australia for the kris sword after Nelson's death — with one of Nelson's nephews, who Adam Brumm discovered moved to the NSW colonies in the 1820s.

The next firm timepoint in the kris sword's history was the late 1980s or 90s, when it was bought at a Brisbane gun show by the collector who then sold it to Adam.

Right now, the kris is in a safe in London as Martyn continues searching for something that nails it as a genuine Nelson artefact.

If confirmed, Adam says it belongs in a museum, but where, he's not sure.

"If we do manage to find some sort of evidence that this belonged to Lord Nelson, it becomes one of these national treasures of Britain and of English history.

"On the other hand, it's clearly been in Australia for a very long time, so then it becomes an object of interest for Australia and our history as well.

Even without confirmation of Nelson's ownership, there are huge holes in the kris sword's known history, and Adam would like to "science the hell out of it" to fill those gaps.

Carbon dating could help ascertain when the sword was made. Tiny flakes of ash trapped in the blade from the forging process might be extracted and dated.

New techniques in DNA extraction and analysis may also give information about those who wielded the sword. In theory, anyone who held the hemp binding around the hilt will have left traces of DNA trapped in the fibres.

Adam admits the ideas sound "outlandish" and may not yield results, but he's keen to give them a go.

"I love a mystery to work on as an archaeologist and really as a scholar," he says.

"And to me, this is one of the most enigmatic objects I've come across."

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