For thousands of years the island was inhabited by Aborigines who had made their way across the Lowrie and Warwick Channels from Arnhem Land and sparsely settled the island living a simple hunter gatherer existence.
Groote Eylandt was first sighted by Europeans in 1623 when the Dutch ship Arnhem, under the captaincy of Willem van Coolsteerdt (not exactly a household name in the history of Australian exploration) sailed along the west coast of the Gulf of Carpentaria. At this time it remained unnamed and it wasn't until Abel Tasman explored the coast in 1644 that it was given the name Groote Eylandt. In 1803, while circumnavigating Australia, Matthew Flinders travelled around the island.
Of course the Europeans were not the island's first visitors. Fishermen from the Indonesian archipelago had been coming to the island for thousands of years to fish and catch beche-de-mer (trepang). This was stopped by the Australian government in 1907 although, even today, Indonesian fishermen still drift into the waters of the Gulf.
There was little interest in the island during the nineteenth century but during the twentieth century it has seen successive waves of missionaries, military personnel and miners.
The first mission on the island was established at Emerald River in 1921 by the Anglican Church Missionary Society. It was moved to Angurugu in 1943 after the RAAF took over the Emerald River airstrip as part of Australia's northern defence. The mission continued until 1979 when the community became a self-governing Aboriginal Town Council.
Another settlement at Umbakumba (Port Langdon) on the northeast coast was established in 1938 and it soon became a Qantas flying boat base.
The economy of the island changed dramatically with the discovery of manganese near Angurugu. As early as 1803 Matthew Flinders had observed the presence of ironstone and quartz on the island. In 1907 the South Australian Government Geologist noted manganese outcrops but it was not until 1955 that commercial geologists took manganese samples from the island. Between 1960 and 1963 negotiations between BHP and the Church Missionary Society (representing the local Aborigines) worked out royalty payments and agreements which allowed large scale mining to start. In 1964 the BHP subsidiary, Gemco (Groote Eylandt Mining Company) was granted leases on the island and in 1966 the first shipment of manganese ore left the island bound for a processing works at Bell Bay near George Town in Tasmania. The manganese mined on the island is now exported to countries like Japan and the USA. The island produces over 2 million tonnes of manganese each year. This is about 10 percent of the world's total production.
Groote Eylandt is not open to the public. The local Aboriginal Land Council has not encouraged the development of tourism.
If you wish to read further on the history of the island Dr Keith Cole has written five books on the region including the excellent Groote Eylandt Aborigines and Mining: A study in cross-cultural relationships which he self-published in 1988.