[9][10] Historians and academics widely criticised the project, claiming that it was "attempting to balance out the violence committed in the name of empire with its supposed benefits".

[11][12][13] The project also received criticism for failing to engage with the wider scholarship on empire and not submitting itself to peer scrutiny and rigorous academic debate.

[18] In contrast, Trevor Phillips in The Sunday Times said that it "carries the intellectual force of a Javelin antitank missile", stating that he "find[s] it hard to disagree" with Biggar's thesis.

[19] Jonathan Sumption in the Literary Review described it as "an important book as well as a courageous one" and said that "in general, [Biggar's] approach is objective and he fairly addresses the contrary arguments".

[20] In The Daily Telegraph, Tim Stanley considered the book "thoughtful" and "compelling", one that introduced facts, some of which he was unaware of, indicating that "much that is benign about our civilisation has been forgotten", but concluded that Biggar "is spoiling for a fight, and I fear he's going to get one".

[21] Biggar replied in the same journal, accusing Lester of "political bias, smearing by association, the erection of strawmen, careless reading, misrepresentation, misunderstanding, unsupported assertions, a disappointing absence of open thoughtfulness, and a striking lack of critical self-awareness".

[22] Biggar was appointed Commander of the Order of the British Empire in the 2021 Birthday Honours, for services to higher education.