On 29 September 1923, the addition of Mandatory Palestine increased the British Empire to its greatest size: nearly fourteen million square miles (150 times the size of Great Britain, a quarter of the world’s land area). It now contained 460 million people, a fifth of the world’s population. Yet, as this book’s subtitle makes clear, it was also an empire in crisis, beset by debt and doubts. To explain why, and to shine a light on the nature and workings of Britain’s empire, Matthew Parker ranges from east to west to ‘immerse the reader’ in the moment.

It’s a clever concept that works extraordinarily well. Of course, context in history is everything and, to give it, Parker moves back and forth in time to explain, for example, the story behind Ocean Island, a tiny Pacific territory close to the international date line, which on 29 September was the first place in the British Empire over which the sun rose. Just six miles in circumference and with a population of only a thousand, Ocean Island was important for the sole reason that its soil was mostly pure phosphate, ‘an immensely valuable, even crucial resource for the wider empire’.

To exploit this resource – vital as a fertiliser for farmers in Australia and New Zealand – the Pacific Phosphate Company rented land from the islanders at ridiculously low rates, which enabled it to make huge profits. By removing the soil from under the islanders’ feet, the company was destroying the island and leaving behind a rocky wasteland. Various local officials tried to intervene, with one making the ‘strongest representations to the colonial office in favour of the oppressed landowners’. A fund was set up for the islanders’ benefit, and in 1923 the colonial secretary ruled that ‘native interests cannot be sacrificed in order to secure any advantage financial or other’. Yet ultimately commercial interests won out and the locals were blackmailed into signing over the rest of their land and moving to Rabi Island in the Fuji archipelago, 1,600 miles away.

The big event of October 1923 was the Imperial Conference in London, to which representatives from the dominions (including the Irish Free State) and India were invited. On the agenda were foreign policy and imperial defence, improvements in trade and communication, and emigration. Yet it quickly became clear that, partly