Neapolitan chord topic

In music theory, a Neapolitan chord (or simply a "Neapolitan") is a major chord built on the lowered second (supertonic) scale degree. It most commonly occurs in first inversion so that it is notated either as ♭II or N and normally referred to as a Neapolitan sixth chord. The Neapolitan chord is so-called because it is associated with the so-called "Neapolitan school", which included Alessandro Scarlatti, Pergolesi, Paisiello, Cimarosa and other important 18th-century composers of Italian opera... full article at wikipedia