The last survey of North Sentinel Island's population was in 2012, estimated to be between 50-100 people. North Sentinel Island has an official population of 39, but the most recent estimate in 2018 says there could be as many as 400 people. The island is inhabited by indigenous people in voluntary isolation called the Sentinelese. It is challenging to ascertain the exact number of residents, as most take to the wild and do not register themselves as inhabitants in a state-recognized home. The people also defend their isolation by force, meaning they are highly hostile to foreigners that seek to destroy their way of life.
North Sentinel island is one of the Andaman islands, which is an archipelago in India that also includes South Sentinel island. The act of 1956 protects the rights of the indigenous inhabitants by prohibiting travel to the island and around 9km surrounding the island's waters. This is because people have isolated themselves from the rest of the world, meaning they are highly susceptible to contracting contagious diseases that could otherwise be cured with modern medicines and antibodies.
Although they are officially considered to be part of India for administrative purposes, the reality is much different. In practice, the authorities respect the islander's right to their privacy and do not restrict their ability to defend themselves and monitor the activities of those getting too close. This also includes no recourse to venturing to the island and being injured or killed in the process.
The Onge, which is one of the other native peoples of the area and islands, are aware of the North Island's existence and have strong cultural ties and similarities amongst them. The Onges people were responsible for bringing British explorers to the islands, but found that no one could speak the Sentinelese language. 2 notable visits were made in 1771 and again in March of 1867. Famously, an Indian merchant ship was shipwrecked near the reef of the island and had almost 106 surviving souls on board. They were famously able to fend off attack by the native Sentinelese people and were rescued by the British Royal Navy.
The native people of North Sentinel Island were able to survive the 2004 Indian Ocean Earthquake, and, even more impressively, were able to continue living through the aftereffects. This was sheer determination, as a tsunami uplifted and flooded the island. Indian officials had sent a helicopter during this time to survey the area but were met with stones and spears. The Sentinelese were said to have adopted them even after the tsunami had disturbed sacred fishing grounds that made up much of their diet.
In 2018, the Indian government temporarily lifted travel bans across the islands to encourage tourism. Allen Chau, a 26-year-old Christian Missionary, had illegally plotted a course to the island to spread the religion. He was killed and his crew was held captive and returned to Indian officials.