The Muse in Arms is an anthology of British war poetry published in November 1917 during World War I. It consists of 131 poems by 52 contributors, with the poems divided into fourteen thematic sections. The poets were from all three branches of the armed services, land, sea and air, from a range of ranks and from many parts of the UK. Twenty of the poets who contributed to this volume died during the war. The editor was the journalist and author Edward Bolland Osborn (1867–1938), and the book was printed in London by the publishers John Murray. This anthology was one of several collections of war poetry published in the UK during the war. It "achieved large sales", and was reprinted in February 1918. It has been referenced in several analyses of First World War poetry and has been described as "the most celebrated collection of the war years".

The Gloucestershire Regiment, commonly referred to as the Glosters, was a line infantry regiment of the British Army from 1881 until 1994. It traced its origins to Colonel Gibson's Regiment of Foot, which was raised in 1694 and later became the 28th Regiment of Foot. The regiment was formed by the merger of the 28th Regiment with the 61st Regiment of Foot. It inherited the unique distinction in the British Army of wearing a badge on the back of its headdress as well as the front, a tradition that originated with the 28th Regiment after it fought in two ranks back to back at the Battle of Alexandria in 1801. At its formation the regiment comprised two regular, two militia and two volunteer battalions, and saw its first action during the Second Boer War.