The Delta blues is one of the earliest styles of blues music. Born in southern Mississippi, Delta blues was first recorded in the late-1920s. String instruments (such as the slide guitar) and harmonicas dominated the music, while the vocals were passionate and fiery. Recorded delta blues is mostly one person singing and playing instruments, though bands were more common in performances. Delta blues spread out across the country, giving rise to a host of regional variations, including Chicago and Detroit blues.