Final known words of researcher who studied cannibal tribe before disappearing

On November 19, 1961, the son of New York's then-governor vanished while exploring a remote region in New Guinea.

His ultimate fate has remained a mystery for 64 years and is a story which involves encounters with a tribe that practised ritual cannibalism and numerous theories, both plausible and downright bizarre.

So what happened to Michael Rockefeller?

The third of seven children born to New York governor and Vice-President Nelson Rockefeller, Michael had a passion for exploring and collecting fine art.

His passion would lead him to cross paths with the Asmat people, a group of people living in Dutch New Guinea (now South Papua, Indonesia) who were renowned for their skilled woodcarvings.

It would be on one of these excursions to the island of New Guinea where the mystery of Michael Rockefeller began.

The son of a prominent family vanishing in a remote part of the world? The stuff of true crime enthusiasts' dreams (Harvard University)

In November 1961, Rockefeller was embarking on his second journey to the Asmat region of Southwestern Papua alongside anthropologist René Wassing when their canoe capsized around three miles from the shore.

What are the last known words of Michael Rockefeller?

After their 40-foot canoe capsized, Rockefeller and Wassing were faced with a tough decision on what to do next.

Wassing remained at sea and was ultimately picked up by another ship; however, Rockefeller decided he would try and make it ashore.

According to Wassing, Rockefeller fashioned himself a float from a jerry can and the boat's gas can, took out his compass and headed for land.

An example of Asmat woodcarvings, some of which were linked to headhunting rituals (Arne Hodalic/CORBIS/Corbis via Getty Images)

"I think I can make it," were the last words Rockefeller told Wassing, who watched as his travelling companion vanished into the distance.

What happened to Michael Rockefeller?

Given that he was the son of a prominent and important man in America, extensive searches for Rockefeller were conducted, however, none yielded any results.

The 23-year-old was declared legally dead in 1964, with no remains or proof of his death being recovered.

Rockefeller's twin sister Mary has publicly stated her belief that the young explorer had been overambitious in his attempts to make it ashore and drowned. However, not everyone agrees.

Theories about Rockefeller's death include drowning and cannibalism (President and Fellows of Harvard University; Peabody Museum of Archeology and Ethnology)

Numerous other theories have been put forward, including the idea that Rockefeller was killed and consumed by the Asmat people.

One person who supports this theory is author Carl Hoffman, who visited the area and produced the most extensive book on Rockefeller's disappearance, titled Savage Harvest: A Tale of Cannibals, Colonialism, And Michael Rockefeller's Tragic Quest.

According to Hoffman, Rockefeller was most likely killed as part of a headhunting ritual in revenge for Dutch colonial authorities killing five Otsjanep residents.

"The Asmat did not kill Michael Rockefeller because they felt murderous. And they didn't kill him because they were hungry, and they needed a bite to eat," Hoffman explained during an interview with LADbible earlier this year.

"They killed him for these complex historical and cultural reasons... It's ironic, in a way, the things that drew Michael to the Asmat are the things that killed him."

Carl Hoffman's book Savage Harvest is available to buy here.