There's grisly irony in the fact that one of the country's more nefarious human remains traders had his own head lopped off.
During the early 19th century Joe Rowe, a tough-arms-dealing frontier character known as "Te Rauparaha's Pakeha", had a store on Kapiti Island.
He'd display toi moko - mummified preserved heads - for interested buyers.
But familiar moko patterns on some of Rowe's stocks caught the eyes of a visiting group from Ngati Tuwharetoa.
They recognised relations and asked Rowe to return them. A blunt refusal sealed his fate.
On a trading trip up the Whanganui River he was captured. Others in his party were spared but Rowe was killed, his head preserved and taken back to Taupo.
It was simple and direct form of payback, says Te Papa archaeologist Amber Aranui.
"It was utu. They said 'we'll fix you,' and they did."
Aranui, who works for the museum's's international repatriation programme, this week returned from Europe with a number of heads and other skeletal remains.
How hundreds of heads and hundreds more individual koiwi, or bones, made it into private, museum and university collections worldwide is largely the 19th century story of what is now understood as trafficking in human remains.
It occurred against a backdrop of developments in medicine and eventual deadends such as comparing skulls to determine intelligence .
Auckland Museum curator Thomas Cheeseman was one of the most prolific traders of his time.
A meticulous records keeper, his letters are held by the Auckland War Memorial Museum.
They spell out how he used bones as international currency to help fill the fledgling museum's halls and display cases, packing up boxes of native flora and fauna for exchanges.
In September 1877, Cheeseman corresponded with a man named Giglioli in Florence, plumping for specimens of South European mammals and birds for Auckland.
As quid pro quo, he wrote: "I could send ... New Zealand bird skins, a very fair collection, NZ insects - a very fine series of coleoptera - including perhaps over 400 species, all well set out... Ethnological specimens relating to the Maori Race - also a series of their crania."
Otago University's Maori Studies chair Professor Paul Tapsell says the records reveal Cheeseman employed agents to go "grave robbing".
Letters to Cheeseman from his men in the field noted how they took care to avoid detection and hid themselves.
In a Public Archaeology journal article Brian Hole says there were three principal reasons driving the demand. Profit for men such as Rowe and artistic appreciation for major collectors such as Horatio Robley who called it a "remarkable work of art," were two reasons.
However, collection was related to popular scientific theories of the time which "strongly presumed that human populations were naturally to be ordered in a racial evolutionary taxonomy," Hole writes.
Under that system white European races were at the top of the tree followed by the rest of the world's cultures, ordered by colours.
But it wasn't just Pakeha trading skeletal remains, Aranui says.
In the early contact period, before the Treaty was signed, Maori helped meet demand from Europeans with Ngapuhi and Ngati Whatua entering heavily into the trade.
In 1837 a travelling writer, JP Johnson, published a book for potential British migrants.
He recounts an encounter with a chief called Te Hiko o te Rangi, who knew that interest in heads was high aboard Johnson's ship.
Aranui says, "Johnson himself was in competition with the ship's doctor to obtain this toi moko, but in the end the doctor gets one.
"Te Hiko o Te Rangi said to him 'you know, if you still want one I can bring some of my slaves and you can pick one and then in three days you can have one as well'."
By 1840 the trend was for fewer and fewer highborn Maori to take on facial moko.
Te Papa research reveals that during the height of the toi trade if living warriors had distinctive, attractive moko it was likely they'd be targeted during wars and battles.
"We think it's a possibility men weren't moko'd as often for fear of their head being taken," says Aranui.
By the 20th century, the dubious science that had prompted the collection of heads had been discredited.
Te Papa's repatriation programme currently holds 101 toi moko and about 500 individual bones from around the globe.
The ultimate goal is to return "ancestral remains" to their iwi. It's still to be decided what to do with those remains where point of origin can't be determined.
Chief executive Michelle Hippolite says these days the international work is easier, although it still involves diplomacy.
"Fifteen to 20 years ago you'd still be battling to get an audience [with institutions]. These days we send friendly letters of introduction... there's far more willingness to share information and talk to us about how [repatriation] might take place."
The recent blip was France, where the fear was if the city of Rouen's toi moko was allowed to return to New Zealand it would give states such as Egypt a stronger case for mummies or other cultural objects to be returned.
Further complicating matters is a 2002 law which enshrines the principal of inalienability of cultural objects held by museums. In the case of human remains, politicians in Rouen bypassed that law because earlier bioethics legislation outlined that a body can't be an object of collection.
France is the first country Te Papa has dealt with that had to write a specific law for the restitution to occur. A former culture minister blocked Rouen from returning remains in 2007 because of concerns it undercut France's own heritage laws.
Senator Catherine Morin-Desailly was Rouen's deputy mayor and championed repatriation by introducing the 2010 law.
These remains were once people, not things.
"You do not keep a collection of insects as you keep people, there is a difference," she remarked.
"This was a demand from a contemporary people. These human remains have been turned into objects of art using very bad, violent and barbaric methods. They are the result of the horrible and despicable human trafficking of the time."
But she was equally clear that though this repatriation was the right moral course to take, repatriating other non-human cultural objects would never have gained her or her countrymen's wider support.
Her law clears the way for the return of all other Maori human remains in French institutions, thought to number between 12 and 20.
For the remains Te Papa repatriated from Norway, Sweden, Rouen and Germany, the real grunt work starts now.
Aranui's team will have to establish, as far as they can, where the remains came from. It's a detective job that can take years, as ship logs are trawled through, migration paths are marked and other tips and hints are followed.
But it's a job which gives dignity back to the long-dead, she says.
How toi moko were made
In pre-European contact times the preservation of toi moko was a practice used to honour high-ranking nobles. Te Papa archaeologist Amber Aranui says heads were treated as living people, put in sacred places, venerated and brought out for special occasions specific to them.
Vanquished warriors heads were also preserved and could be used to make future peace with tribes once they were returned. Bones of enemies could be treated with contempt. Heads were used by children for play or mounted around pa for insult.
In 1894 Reverend Philip Walsh published a study of how heads were preserved, drawing together earlier reports on the subject.
Not all accounts were consistent but Rev Walsh wrote that the brain, tongue, eyes and as much as possible of the flesh was carefully extracted before the cavities were stuffed with flax.
The head was steamed, sometimes in ahangi oven similar to that used for food before going through a drying process using woodsmoke and the sun. Finally the head was anointed with oil and hair combed into a knot ornamented with feathers.
Yvonne Tahana travelled to France with the assistance of Te Puni Kokiri