It is a truth universally acknowledged that the detonation of devastating new weapons above the Japanese cities of Hiroshima and Nagasaki on 6 and 9 August 1945 brought an end to World War II.

What may be less well remembered, however, is that the ground-breaking technology behind the atomic bomb – along with that of a host of other Allied wartime innovations, from airborne radar to the codebreaking ‘bombe’ – was actually the product of an extraordinary and long-running collaboration, between British scientific inventiveness and American industrial might.

In our cover story, Larrie D Ferreiro explains how this ‘special relationship’ between British and American combat scientists and engineers was rooted in strategy laid out by Winston Churchill in the war’s earliest days, and how it produced many of the advances that enabled the Allies to achieve final victory.

Elsewhere, in our latest two-part special, Paul Rahe examines the history of the Peloponnesian War, the epic contest between Athens and Sparta during the 5th century BC that signalled the end of the ‘Golden Age’ of ancient Greece.

Also in this issue, Graham Goodlad reveals how the partnership forged by the late-Victorian commanders Roberts and Kitchener helped to win the Anglo-Boer War, but brought controversy in its wake; and William E Welsh describes the events that led to the Battle of Baugé, the bloody encounter in 1421 that saw Scottish forces achieve a notable victory in the Hundred Years War.

And, finally, to mark the 50th anniversary of the withdrawal of American troops from Vietnam, Taylor Downing looks back at the end of a conflict that had stretched across almost 30 years.

We hope you enjoy the issue!