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On North Sentinel Island, a spit of coral and rock in India’s far-flung Andaman and Nicobar Islands, lives one of the planet’s most isolated groups of people. They are a tribe of hunter-gatherers known as the Sentinelese, a name given to them because no one has any clue what they call themselves. Nor does anyone know how many of them there are; the best guesses put their population at fewer than 100.

This tiny community is now at the center of global attention thanks to a 26-year-old American missionary named John Allen Chau. Chau traveled to the island this month, hoping to convert the Sentinelese to Christianity. They killed him instead.

Chau’s story illustrated how hard it is to keep modern society from penetrating any corner of the Earth — even the ones that want nothing to do with it.

The Sentinelese — believed to be direct descendants of a migration from Africa some 50,000 years ago — have historically been hostile to visitors, and for good reason. Encounters with outsiders, especially under the aegis of 19th-century British colonial authorities, decimated the aboriginal populations of the Andaman and Nicobar Islands. Like so many other indigenous peoples during the age of European empires, the tribes of the islands were unprepared for foreign diseases and vulnerable to the explorers who saw them as specimens of primeval man — subjects for zoological study, not human compassion.

In the 1970s, a National Geographic film director who approached North Sentinel Island with a team was hit in the leg by an arrow. In 2006, two marooned Indian fishermen were killed there, their bodies reportedly propped up on the beach in a lurid display. Sporadic “gift-giving” missions carried out by anthropologists stopped taking place by the 1990s, with academics and authorities convinced the Sentinelese were better off left alone.

The tribe, along with a handful of other aboriginal communities in the archipelago, lives beyond the pale of the Indian state, which has outlawed visits to the island to preserve its inhabitants' isolation.

But none of this was about to deter Chau. He paid local fishermen to help him evade Indian Navy patrols, then, once close enough, paddled to the island in a kayak and attempted to make contact. According to a diary he kept, Chau sang devotional songs and proffered gifts of scissors, fish and a soccer ball to the people he saw. In response, at least one person shot an arrow that punctured the American’s waterproof copy of the Bible.

“Lord, is this island Satan’s last stronghold where none have heard or even had the chance to hear your name?” he wrote in the diary, which was provided to The Washington Post by his mother.

The morning after Chau’s last trip to the island, the fishermen who conveyed him to North Sentinel saw his body being dragged around a beach and buried in the sand. Indian authorities arrested five of the fishermen for helping Chau make the illegal and fatal journey, and they now are puzzling over what to do about retrieving his remains. Attempting contact is a fraught endeavor that could lead to further violence and expose the Sentinelese to outside contagion. A police team that approached the island on Friday reportedly saw a number of the Sentinelese standing watch, bows at the ready.

“We don’t have any plan to go on the land or do any kind of confrontation,” said Dependra Pathak, the police chief for the Andaman and Nicobar Islands, to The Post’s Joanna Slater over the weekend. “We have to move with utmost sensitivity and care.” The incident involving Chau had “to create a good amount of stress” among the Sentinelese, Pathak told The Post.

In eras past, stories of martyrdom helped spread Christianity through certain parts of Asia. But Chau’s demise has mostly inspired outrage, with critics in India and elsewhere riled by the selfish foolhardiness of his mission.

The Sentinelese have shown again and again that they want to be left alone, and their wishes should be respected,” said Stephen Corry, the director of indigenous-rights group Survival International, in a statement. “The British colonial occupation of the Andaman Islands decimated the tribes living there, wiping out thousands of tribespeople, and only a fraction of the original population now survive. So the Sentinelese fear of outsiders is very understandable.”

There is certainly far more sympathy for the plight of populations like the Sentinelese than there was in the past, but indigenous communities like theirs are hardly any safer than before. In many places, the perils posed by climate change and the resource demands of developing countries have only deepened the vulnerability of isolated tribes.

In Brazil, far-right President-elect Jair Bolsonaro has vowed to scrap the country’s indigenous affairs department in a bid to boost the expansion of agribusiness and logging companies. “If I become president, there will not be one centimeter more of indigenous land,” he once declared. Brazil’s Amazon region is home to roughly 100 “uncontacted” tribes — more than any other country on Earth — and activists are now warning of a new “genocide” should Bolsonaro follow through on his promises.

In many cases, though, indigenous communities are undermined not by faraway political fiat, but by the pressure of a world inexorably closing around them.

T.N. Pandit, an Indian anthropologist who spent decades studying the aboriginal peoples of the Andamans, lamented the effects outside exposure has had on them. In an interview with the New York Times last year, he pointed to the steady depletion of the Jarawa tribe, neighbors to the Sentinelese, after extended contact with outsiders. Their numbers have thinned; fewer people among the younger generation know the skills or languages of their ancestors.

“In the course of time, these communities will disappear,” Pandit said. “Their cultures will be lost.”

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