Sathnam Sanghera’s Empireland, a journey through Britain’s imperial past, has been a bestseller since it was pubished last month, acclaimed by critics as “unflinching … moving and stimulating” (the Guardian), and “excellent” and “balanced” (the Sunday Times). And yet, from the British public the author has received handwritten hate mail, and thousands of abusive tweets from “imperially nostalgic racists”, as he succinctly replied, some of them verging, he says, on death threats.

“If you’re brown and you talk about race in this country, you just get loads of shit, all the time,” says Sanghera, a journalist for the Times who is also the author of the memoir The Boy With the Topknot and the novel Marriage Material. In 2019, he presented a documentary for Channel 4 on empire, looking at the Amritsar massacre, and got “hundreds, if not thousands of messages and letters and complaints about that. So I got a small taste of it then. I knew it would be insane. But it’s escalated. It’s been vicious.”

Sanghera has shared some of the messages and letters he has received on his Twitter account, describing the abuse as “proof we need to have this conversation”. The attacks, he says, are a fraction of those directed at David Olusoga, the historian and broadcaster whose last book Black and British examined the relationship between the British Isles and the people of Africa and the Caribbean.

“Empire has been weaponised by the right wing, ever since Black Lives Matter. Now there’s this idea that you need to be proud of imperial history to be proud of the country and vice versa. It’s become a proxy for patriotism and race,” says Sanghera. “When you talk about empire, you’re talking about race, really. You’re talking about white people conquering brown people. And so when you have brown people like David or me talking about empire, it triggers people in a really deep way. David challenges the hierarchy of empire. But he also challenges the way the imperial story has always been told, which is a 50-year-old white man on TV, often getting off a train in India; a nostalgic view. Suddenly there’s brown people taking ownership of this story and it’s really triggering for so many people.”