The regiment was posted to Kabul in 1840 during the First Anglo-Afghan War and was part of the advance-guard during the January 1842 retreat. Viewed as one of the worst British military disasters of the 19th century, by breaking the myth of the army's invincibility it also allegedly facilitated the 1857 Indian Rebellion. The regiment was engaged in a continuous running battle in thick snow, suffering heavy casualties, among them Captain Thomas Leighton, killed on 10 January and commemorated in All Saints' Church, Northallerton.