Little is known about the exact origin of the music now known as the blues. No specific year can be cited as the origin of the blues, largely because the style evolved over a long period and existed in approaching its modern form before the term blues was introduced and before the style was thoroughly documented. Ethnomusicologist Gerhard Kubik traces the roots of many of the elements that were to develop into the blues back to the African continent, the "cradle of the blues". One important early mention of something closely resembling the blues comes from 1901, when an archaeologist in Mississippi described the songs of black workers which had lyrical themes and technical elements in common with the blues.
African roots
There are few characteristics common to all blues, as the genre takes its shape from the distinctive attributes of each individual performance. Some characteristics, however, were present prior to the creation of the modern blues, and are common to most styles of African American music. The earliest blues-like music was a "functional expression, rendered in a call-and-response style without accompaniment or harmony and unbounded by the formality of any particular musical structure". This pre-blues music was adapted from the field shouts and hollers performed during slave times, expanded into "simple solo songs laden with emotional content".
Many of these blues elements, such as the call-and-response format, can be traced back to the music of Africa. The use of melisma and a wavy, nasal intonation also suggests a connection between the music of West and Central Africa and the blues. The belief that blues is historically derived from the West African music including from Mali is reflected in Martin Scorsese’s often quoted characterization of Ali Farka Touré’s tradition as constituting "the DNA of the blues".
Perhaps the most compelling African instrument that is a predecessor to an African-American instrument is the "Akonting", a folk lute of the Jola tribe of Senegambia. It is a clear predecessor to the American banjo in its playing style, the construction of the instrument itself and in its social role as a folk instrument. The Kora is played by a professional caste of praise singers for the rich and aristocracy (called griots or jalis) and is not considered folk music. Jola music may not have been influenced much by North African/Middle Eastern music, which may point to African American music not being, according to Sam Charters, related to kora music. The music of the Akonting and that played by on the banjo by elder African-American banjo players, even into the mid 20th century is easily identified as being very similar. The akonting is perhaps the most important and concrete link that exists between African and African-American music.
While the findings of Kubik and others clearly attest to the essential Africanness of many essential aspects of blues expression, studies by Willie Ruff and others have situated the origin of "black" spiritual music inside enslaved peoples' exposure to their masters' Hebridean-originated gospels. African-American economist and historian Thomas Sowell also notes that the southern, black, ex-slave population was acculturated to a considerable degree by and among their Scots-Irish "redneck" neighbors. Additionally, there are theories that the four-beats-per-measure structure of the blues might share its origins with the Native American tradition of pow wow drumming.
Other African influence
The historian Sylviane Diouf and ethnomusicologist Gerhard Kubik identify Islamic music as an influence on blues music. Diouf notes a striking resemblance between the Islamic call to prayer (originating from Bilal ibn Rabah, a famous Abyssinian African Muslim in the early 7th century) and 19th-century field holler music, noting that both have similar lyrics praising God, melody, note changes, "words that seem to quiver and shake" in the vocal chords, dramatic changes in musical scales, and nasal intonation. She attributes the origins of field holler music to African Muslim slaves who accounted for an estimated 30% of African slaves in America. According to Kubik, "the vocal style of many blues singers using melisma, wavy intonation, and so forth is a heritage of that large region of West Africa that had been in contact with the Islamic world via the Maghreb since the seventh and eighth centuries." There was particularly a significant trans-Saharan cross-fertilization between the musical traditions of the Maghreb and the Sahel.