Anonymous 4, the renowned American female a cappella quartet known for their mastery of medieval music, made their final Tiny Desk concert appearance in 2015 before disbanding. The group, formed in 1986 and based in New York City, gained acclaim for their pure and accurate vocal sound, often performing 13th-century Christmas music as well as premiering works by modern composers like John Tavener and Steve Reich.

Over the course of their illustrious career, which spanned 25 years and included 21 albums, Anonymous 4 captivated audiences with their unique sound. They performed across North America and at major international festivals, solidifying their legacy as pioneers in medieval music interpretation.

In addition to their traditional repertoire, Anonymous 4 collaborated with artists like the Chilingirian Quartet, The Mountain Goats, and Christopher Tin, showcasing their versatility and willingness to explore diverse musical genres.

Their final album, "1865," featuring songs from the Civil War with accompaniment by Bruce Molsky, marked the conclusion of their recording and touring endeavors as a group. The quartet disbanded at the end of the 2015–2016 season, leaving behind a rich legacy in the world of vocal music.