As a part of the Irish folk group Solas, Karan Casey defined herself as one of the genre's best, joining the distinguished ranks of fellow female singer/songwriters such as Maire Brennan (Clannad), Mairéad Ní Mhaonaigh (Altan), Sharon Shannon, and Karen Matheson (Capercaillie). After leaving Solas in 1999, Casey enjoyed a successful solo career, issuing a string of acclaimed efforts like Distant Shore (2003), Ships in the Forest (2008), and Hieroglyphs That Tell the Tale (2018) that stand at the nexus of contemporary and traditional folk music.

Karan Casey grew up singing with her family in the southeastern side of Waterford in the Irish village of Ballyduff Lower. As a child, she sang in the church choir, but turned to the piano as a young adult. While studying voice and piano at the University College Dublin and later at the Royal Irish Academy of Music in the late '80s, Casey was singing Ella Fitzgerald standards in a jazz duo at a local pub. She also started her own Irish group called Dorothy. She credits jazz music for allowing her to wholly approach and understand her ability to sing traditional Irish folklore. Dublin, however, was not the place for her to continue her exploration.

In 1993, Casey emigrated to New York to find herself studying once again as a jazz music major at Brooklyn's Long Island University. Around this time, she rediscovered her fondness for Irish traditional music and made the rounds singing in locals bars in Manhattan. Such passion led Casey to briefly play with the New York-based band Atlantic Bridge, but by the end of 1994, she'd joined Seamus Egan, John Doyle, John Williams, and Winifred Horan to form Solas. The band quickly received critical acclaim and recorded three albums with Shanachie. Solas also found themselves touring American, Europe, and Japan, playing alongside greats such as Bela Fleck, the Chieftains, Iris DeMent, and Donal Lunny.

In the midst of this, Casey still found time to record a solo album called Songlines, that appeared in 1997. She left Solas two years later and released her sophomore solo effort, Winds Begin to Sing, in 2001. Distant Shore appeared in 2003, with Chasing the Sun, which included songs that she learned from her mother and maternal grandmother, arriving in 2005. After playing shows in North America and Europe (and appearing as a frequent guest on Garrison Keillor's A Prairie Home Companion), Casey briefly returned to Solas for the group's 2006 release Reunion. In 2008, she issued her fifth solo album, Ships in the Forest, on Crow Valley Music, a label she started with her husband, Irish concertina player Niall Vallely. 2010's well-received Exiles Return saw Casey reuniting with her Solas bandmate John Doyle, while 2014's inward-looking Two More Hours featured a set of entirely self-penned works. Hieroglyphs That Tell the Tale appeared in 2018, and included guest spots from Karen Matheson, Niamh Dunne, Pauline Scanlon, Maura O'Connell, and Aoife O Donovan. 2022 saw Casey collaborate with composer Harry Escott on a version of the Irish ballad "Grace" for the British drama/romance film Ali & Ava. ~ MacKenzie Wilson & James Christopher Monger, Rovi