A prominent Canadian-American author, who has long claimed Indigenous ancestry and whose work exposed “the hard truths of the injustices of the Indigenous peoples of North America”, has learned from a genealogist that he has no Cherokee ancestry.

In an essay titled “A most inconvenient Indian” published on Monday for Canada’s Globe and Mail, Thomas King said he had learned of rumours circulating in recent years within both the arts and Indigenous communities that questioned his Cherokee heritage.

In mid-November, he met with members of the Tribal Alliance Against Frauds (Taaf), a group based in the state of North Carolina that exposes perpetrators of Indigenous identity fraud. King says this group was the main source of the rumours.

The genealogist working with Taaf told King she found no evidence of Cherokee ancestry on either side of his family lineage. King says he accepts the findings.

“It’s been a couple of weeks since that video call, and I’m still reeling. At 82, I feel as though I’ve been ripped in half, a one-legged man in a two-legged story,” he wrote. “Not the Indian I had in mind. Not an Indian at all.”

King, a California-born academic, writer and activist, has lived in Canada since 1980, when he took a job in Alberta teaching Indigenous studies at the University of Lethbridge. He rose to prominence with work that Canada’s governor general said displayed “formidable wit to explore the social, economic and political dimensions of the modern Aboriginal experience”.

King has long said he grew up hearing a story that his father, Robert King, was not his biological father. Instead, Thomas King’s grandfather was Elvin Hunt, a man believed to have Cherokee ancestry. But the genealogist working with Taaf found no evidence of Cherokee ancestry on either side of King’s family lineage.

King won the 2014 RBC Taylor prize for non-fiction for his book The Inconvenient Indian and in 2020 won the Stephen Leacock memorial medal for humour for his work Indians on Vacation. That same year, he was promoted to companion of the Order of Canada, commended for his “prolific and groundbreaking work [which] continues to enrich our country’s culture, and has changed our perception of Canadian history”.

In an interview with the Globe and Mail published on Monday, King said he intended to return the National Aboriginal Achievement award, which he received in 2003. “The rest of my awards are based on my writing, not my ethnicity,” he said.

King is the latest prominent figure whose claims to Indigenous ancestry have been disproven. Recently, a Canadian Broadcasting Corporation investigation claimed folk singer Buffy Sainte-Marie was born in Massachusetts to white parents, not to Cree parents as she had long claimed.

King says he never intentionally misled people, instead genuinely believing he had Cherokee ancestry.

“Taaf suggested that I might want to offer up an apology for my life, but an apology assumes a crime, an offence, a misdeed,” he wrote in his essay. “And I don’t think that’s appropriate. Throughout my career – activist, academic, administrator, writer – I’ve conducted myself in the belief that I was mixed-blood Cherokee.”

But he wrote that after seeing the evidence, if he chose to withhold that information “then an accusation of fraud would have merit”.