The Swell Season is a folk rock duo formed by Irish (Ireland) musician Glen Hansard and Czech (Czech Republic) singer and pianist Mark�ta Irglov�. "The Swell Season" name is derived from Hansards favourite novel by Josef ?kvoreck� from 1975 bearing the same title. Their debut album (The Swell Season (album)) goes by the same name.

Since their rise to prominence after starring in the 2007 film Once (Once (film)), they increasingly referred to themselves as "The Swell Season" in promotion of their performances until it has unambiguously become the formal name of their collaboration in 2008. (Notably, they still used their separate names when they contributed their cover of Bob Dylans "You Aint Goin Nowhere" to the 2007 soundtrack (Im Not There (soundtrack)) of Im Not There.)