World War I (which lasted from July 28, 1914, to November 11, 1918) was a conflict between two groups of nations: the Allies and the Central Powers. The Allies consisted of dozens of nations, largely led by England, France, Russia, Italy, Japan, and the United States, while the Central Powers consisted of Germany, Austria-Hungary, the Ottoman Empire, and Bulgaria. It was the first major conflict to use mechanized weapons such as machine guns and heavy artillery and relied heavily on trench warfare. It was also the first truly global conflict, killing an estimated 17 million soldiers and civilians.

One significant aspect of the war reflected throughout In Memoriam is the emphasis on trench warfare. Each side of the war dug lengths of trenches to house their soldiers in bunkers, keep their weaponry, and provide some protection in between battles. The trenches were notorious for their unhygienic conditions, rats, mud, and lack of shelter from the elements. Ellwood and Gaunt repeatedly refer to “No Man’s Land,” which is the area located between the Allied and the Central Powers’ trenches. The land was destroyed and became littered with dead bodies, and it was also lined with barbed wire to make it nearly impossible to cross.