Neapolitan Chord - Origin of The Name

Origin of The Name

Especially in its most common occurrence (as a triad in first inversion), the chord is known as the "Neapolitan sixth":

• The interval between the bass note and the root of the chord is a minor sixth. For example, in the key of C major or C minor the chord consists of D♭ (the root note), F (the third of the triad), and A♭ (the fifth of the triad) – with the F in the bass, to make it a ♭II6 or N6 rather than a root-position ♭II. The interval of a minor sixth is between F and D♭.

• The chord is called "Neapolitan" because it is associated with the Neapolitan School, which included Alessandro Scarlatti, Pergolesi, Paisiello, Cimarosa, and other important 18th-century composers of Italian opera; but it seems already to have been an established if infrequent harmonic practice by the end of the 17th century, used by Carissimi, Corelli, and Purcell. It was also a favorite idiom among composers in the Classical period, especially Beethoven, who extended its use in root-position and second-inversion chords also (examples include the opening of the String Quartet op. 95, the second movement of the Hammerklavier Sonata, and near the beginning and again in the recapitulation of the first movement of the Moonlight Sonata).