A highly evolved and specialised form of blues music that developed out of the Louisiana blues and is known for its laid back rhythms which dominate a music that is simultaneously funky and often lighthearted. Influences from Cajun music or black Creole zydeco music can also be heard in the sound, which has long been based out of Baton Rouge, Louisiana.

Many swamp blues recordings appeared on national labels, such as the Excello Records label of Nashville and began to have some impact on popular music. For example, the Rolling Stones covered Slim Harpo's I'm A King Bee, and Neil Young, among others, recorded Harpo's Rainin' In My Heart. Swamp blues is often cited as a major influence on Creedence Clearwater Revival.

Other significant swamp blues artists include Silas Hogan, Lazy Lester, Lightnin' Slim, Lonesome Sundown and Whispering Smith.

Swamp blues is distinguished from Delta blues, a far more well-known subgenre of the blues that comes from northern Mississippi.