Stories of writers and wolves are finalists for the nonfiction Baillie Gifford prize

LONDON — Literary biographies vie with explorations of extremism, slavery and European wolves on the shortlist for Britain’s leading nonfiction book prize.

The six finalists announced Thursday for the 50,000 pound ($67,000) Baillie Gifford Prize include “The Boundless Deep,” a biography of poet Alfred, Lord Tennyson by Richard Holmes, Frances Wilson’s “Electric Spark,” about Scottish writer Muriel Spark, and acclaimed Australian writer Helen Garner’s diaries, “How to End a Story.”

Also in the running are Jason Burke’s book about 1970s anti-capitalist militants, “The Revolutionists”; Justin Marozzi’s history of slavery in the Muslim world, “Captives and Companions”; and Adam Weymouth’s “Lone Wolf,” which traces a wolf’s 1,000-mile (1,600-kilometer) journey across the Alps in search of a mate.

Journalist Robbie Millen, who is chairing the prize jury, said the six books displayed “candor and courage” in exploring “formidable female novelists, ghastly literary men, a faith-shaken poet, eunuchs, pirates, horny wolves (and) international terrorists.”

The winner will be announced Nov. 4 at a ceremony in London.

Founded in 1999, the prize recognizes English-language books in current affairs, history, politics, science, sport, travel, biography, autobiography and the arts. It has been credited with bringing an eclectic slate of fact-based books to a wider audience.

Last year’s winner was Australian writer Richard Flanagan for his genre-bending memoir “Question 7.” Flanagan turned down the prize money to protest fossil fuel investments by sponsor Baillie Gifford, an Edinburgh-based finance firm.

Baillie Gifford has stopped sponsoring several British book festivals after protests from environmental groups.

Prize director Toby Mundy said the nonfiction award is in talks with Baillie Gifford about extending its sponsorship, due to end this year.

“I would be thrilled for us to continue to be beneficiaries of their philanthropy,” Mundy said, noting that many companies in Baillie Gifford’s position “sponsor golf."

“But they don’t. They sponsor the free exchange of ideas,” he said.