“Lord, is this island Satan’s last stronghold where none have heard or even had the chance to hear your name?” recorded John Allen Chau in a diary of his last days. Chau, a 26-year-old American missionary, wanted to “declare Jesus” to one of the world’s last uncontacted tribes – the Sentinelese, who inhabit the restricted North Sentinel island in the eastern Indian Ocean. The Sentinelese resist external contact and are known to express their will with arrows. On 17 November, they shot Chau dead, as he approached them with a Bible and some gifts. Now his body may not even be able to be retrieved, for fear of spreading disease to the island.

Once, the entire Andamans were perceived as a “Satan’s stronghold”, an abode of a ferocious race that The Travels of Marco Polo caricatures as – “idolaters”, “no better than wild beasts”, who have “heads like dogs, and teeth and eyes likewise”, “ a most cruel generation”, who would eat everybody they could catch. These islands remained a terra incognita until the British colonised them in the late 18th century. A “civilised” race came in close contact with the “savages” – the Great Andamanese, the Onge, the Jarawa, the Sentinelese and the Jangil (extinct by the 1920s). The tribes exhibited an implacable hostility towards strangers, but the charge of cannibalism against them was unfounded. It was merely a misinterpretation of the ritual that some indigenous people practised – cutting and burning the dead to avoid their return as evil spirits.

Their hatred for strangers, which was viewed as a sign of inherent wickedness, was merely a survival strategy. In the past, Malays, Burmese and Chinese visited the Andamans for slaving expeditions. The captured people were sold as slaves in Ceylon, Indo-China and the Malay Peninsula. A hatred for all strangers was the natural result. The British colonisation did nothing to alter this, as the establishment of a penal colony in the Andamans led to reckless deforestation that the tribes people fiercely resisted.

A mix of punitive and friendly measures was adopted to contain them. In the early 1800s, 10 strong groups of the Great Andamanese inhabited a vast territory. They gathered in thousands and undertook three major raids against the British in April and May 1859. The last raid on the Aberdeen convict station (south of Port Blair), known as “the Battle of Aberdeen”, tipped the scales against the tribes. Dudhnath Tewari, a runaway convict whom the Andamanese had admitted to their community a year earlier, betrayed their trust. The tribal warriors faced the pre-warned British soldiers and incurred massive losses. It quelled their organised resistance forever.

By the early 1860s, the Andamanese were huddled up in the “Andamanese home” where food, shelter, medicine and intoxicants were generously extended to them. In 1869, their children ended up in an orphanage. Soon, several epidemics engulfed them– syphilis (1875), ophthalmia (1876), measles (1877), mumps (1886), influenza (1981) and gonorrhoea (1892), which steadily shrank their population, from 3,500 (1858), to 2,000 (1888), 625 (1901), 455 (1911), 209 (1921), and then 90 (1931). Frequent punitive and friendly expeditions across the islands spread alien diseases that caused the death of thousands of tribesmen. The British regularly captured and kidnapped many to train and use them as intermediaries. But most of them died, escaped or contracted diseases.

Soon, the Onges were also subdued. But the Jarawas kept resisting. Between 1910 and the 1920s, several raids were undertaken against the tribe that were intended to exterminate it. The Kachins, headhunters of Myanmar, regularly combed the jungles. During their regime in the islands (1942-45), the Japanese ruthlessly bombed the Jarawa habitat. From 1947 (the year of India’s independence) to 1999, 268 incidents of conflict with the tribe were recorded.

“The men should be armed with shotguns … teargas is essential as the temporary blinding [of the Jarawas] will help our men. The hidden police could pounce on them when their rafts have landed,” reads a memo (20 September 1948) of an officer based on Andaman’s Long Island.

From the 1950s to the 1970s, thousands of mainlanders and refugees were settled in the islands. Indigenous people contracted diseases to which they had no inbuilt immunity and died. By 1961, the Andamanese population had dwindled to 19. Both the Andamanese and the Onge lost their traditional habitats and were finally relocated in permanent settlements.

By the late 1990s, the Jarawas turned “friendly” which made them susceptible to exploitation. Since then, instances of human safaris, sexual molestation, intoxication and exploitation of Jarawa resources have regularly been reported.

While the total population in the Andaman and Nicobar Islands has soared from 30,971 in 1951 to about 400,000, the number of indigenous people (excluding the Sentinelese) in the Andamans has sharply dwindled from a conservatively estimated 4,800 in 1858 to about 674. Now they are on the verge of extinction and fall under the category of the Particularly Vulnerable Tribal Groups (PVTGs).

The history of outsiders’ relations with the indigenous people of the Andamans has a clear pattern – colonisation, exploitation and eventual extermination. If we are to learn anything from our past, it is that the Sentinelese should be left alone on North Sentinel Island.

• Dr Ajay Saini is a researcher and writer who works with isolated indigenous communities