Canada officially recognizes 634 First Nations, comprising nearly 900,000 indigenous people, or about 2.3 percent of the country’s population. They are spread among nearly a dozen language groups, from Mi’kmaq on the Atlantic coast to Dene in the Northwest Territories. First Nations do not include the Inuit of the far north or the Metis, a people of mixed ancestry.

But who is and who is not recognized as an Indian is a hotly debated, hugely complicated issue. The vast island of Newfoundland, roughly the size of New York State, remained a British colony when Canada was formed in 1867. It did not join Canada until 1949 — on the condition that none of its people would be registered as Indians. But thousands of Newfoundlanders traced their ancestry to the Mi’kmaq, the original inhabitants of Canada’s Atlantic coast, who were first encountered by the Breton explorer Jacques Cartier on his 16th-century voyages of discovery.

The Mi’kmaq of Newfoundland fought for decades to be granted status under the Indian Act, which governs Canada’s relations with its indigenous peoples. One band, as individual communities are called, was finally recognized in 1985. Nine remaining Newfoundland bands joined forces and fought the federal government for decades more. They eventually agreed in 2008 to be grouped together as a single band — the Qalipu, which means caribou in Mi’kmaq — with limited rights and no reserve land.

The government established an enrollment process and expected about 10,000 Newfoundland Mi’kmaq to apply. But it received more than 100,000 applications, prompting the government to suspend the process, tighten its criteria and begin a lengthy review of those already approved while applying the stricter rules to those applications not yet reviewed.

On Monday, Indigenous and Northern Affairs Canada, the department that oversees indigenous affairs, sent letters to applicants and announced the results of the review on its website: Only 18,044, or about one in five, of those who applied had been accepted.