The first world war was the first conflict in which aircraft played a major role. The Sopwith Camel, introduced in 1917, was Britain’s most successful fighter plane. It shot down 1,294 enemy aircraft – more than any other Allied plane. Photograph: © 2014 Jim Kay
AL Kennedy’s short story Another Kind of Missing in The Great War anthology is based on this compass, a 1916 Verners Pattern VII compass, which once belonged to Lieutenant C Birdwood of 3rd Battalion, Devon Regiment. All officers serving in the first world war were expected to carry a compass. Photograph: © Walker Books
In 1915 the RMS Lusitania, a British ocean liner, was sunk by a German U-boat 18 kilometres off the coast of Ireland. 1,196 people died. Most of those killed were British and Canadian, but 124 Americans lost their lives. This greatly influenced the USA’s decision to enter the war in 1917. Photograph: Jim Kay
Horses were indispensable to both sides during the war. They were ridden into battle, they carried supplies and they pulled guns and ambulances. However, when war ended, horses were no longer needed. Many were abandoned or sold for meat. Photograph: © 2014 Jim Kay
Throughout the first world war, around 10 million tons of shells were fired. Shells were explosive-filled missiles which killed millions of men and left huge gashes in the landscape. Soldiers who were exposed to shellfire were at risk of psychological breakdown, known as shell-shock. Photograph: © 2014 Jim Kay
Before 1914, women only worked in “female” jobs such as teaching and domestic service. But when war broke out, women were needed to take over from men in factory, transportation and farm jobs public perceptions of women changed, and many countries, including Britain and the USA, introduced the vote from women soon after the war. Photograph: Jim Kay