320.] The teachings and practice of the Netherlands masters spread through Europe rapidly, and some of the masters themselves went into Italy, where they became the apostles of a new artistic religion.

The Netherlands musicians began early to write secular songs in a style which eventually developed into the madrigal.

Frequently they took folk tunes and treated them polyphonically.

Sometimes they used themes of their own invention.

In time musicians of small skill, undertaking to imitate these earliest secular songs, developed the popular form called frottola.