The Life of Riley

An American phrase, first appearing in print around 1902, whose exact origin remains genuinely unresolved despite several competing theories. One points to an Irish ballad from around 1795, "Willy Reilly and His Colleen Bawn," about a poor Catholic farmer who elopes with a wealthy heiress and eventually wins his freedom and fortune. Another points to an 1880s music-hall song, "Is That Mr. Reilly?" by Pat Rooney, imagining what its hero would do if he suddenly came into money. A third suggests it started as unrelated military slang. It became widely popular in America during the First World War, though which of these threads, if any, actually started it off is unknown.