If the United States has a national song form, it may well be the blues. Wailed by solo singers, the thousands of verses of the blues, borne on a single but endlessly varied haunting cadence, fill a regular Mississippi River of song that long since overflowed its banks into jazz, hillbilly, gospel, opera, pop, and rock. The simplicity of the blues form is as remarkable as its vitality. In this the blues is like other national song forms — the austere copla in which Spanish singers have rhymed the whole Iberian experience, the bittersweet stornello that since the early Renaissance has registered the Italian view of the beauties of women and the ironies of love. But the blues is not only the national song of the United States; it is creeping into the ear of the whole world and may become the first international song style. In origin the blues is bicultural, Afro-American or Afro-European: European in that, like the stornello and the copla, it is essentially a rhymed couplet set to a compact strophic melody; African in a score of ways descending cadences, flatted sevenths and thirds (which register the inherited influence of African scales), a polymetered relation between voice and accompaniment, and a playful singing style changing role from phrase to phrase. Thus the blues merges two musical languages into an international patois.
The appeal of this new language is that it speaks of the modern, urban, alienated experience. The blues came into being in the period between 1890 and 1930, as America was changing from a rural agricultural to an urban industrial nation. In this period the majority of blacks were surplus, often migratory, labor — badly paid, ill-educated, ghetto-confined, without civil rights, and subjected to every sort of exploitation and violence. Long before the rest of Western man, the black migratory laborers — who built the levees and the railroads, raised the crops, and worked in the mills — knew what it was to be so economically and culturally underprivileged as to be without family, friends, or community. — Alan Lomax, from the liner notes