The Greencards are a progressive bluegrass band that formed in Austin, Texas, and are currently based in Nashville, Tennessee. The band was founded in 2003 in Texas by Eamon McLoughlin, an Englishman, and Australians Kym Warner and Carol Young. The musicians originally performed in local Austin bars, and soon found increasing acclaim. They have released one independent album, Movin' On, in 2003, and two albums, Weather and Water, and Viridian, on the Dualtone record label. Their fourth album, Fascination, was released on Sugar Hill in 2009. Their fifth album, "Brick", 2011, was self-produced with the direct support of their fans. Pre-production donors were recognized with their names inscribed on the "bricks" that make-up the cover art.

Their debut album, Movin' On, was the recipient of local Texas awards and charted on Americana radio stations. Country Music Television named their follow-up Weather and Water as one of the ten best bluegrass albums of 2005, and The Greencards were invited to tour with Bob Dylan and Willie Nelson in the same year. Viridian would go on to take the number one position on the Billboard magazine's Bluegrass Music Chart, making The Greencards the first international band to ever do so. Viridian was a critically praised album, and was nominated for Best Country Album by the Australian Recording Industry Association. The track "Mucky the Duck" from Viridian was nominated for a Grammy Award at the 50th Grammy Awards.