North German school

The 17th century organ composers of Germany can be divided into two primary schools: the north German school and the south German school (sometimes a third school, central German, is added). The stylistic differences were dictated not only by teacher-pupil traditions, but also by technical aspects such as the quality and the tradition of organ building, and by certain composers who would help spread national styles by travelling and learning from other countries' styles.

The composer who is now considered the founder of this school is Jan Pieterszoon Sweelinck, a Dutch composer (a student of his father Pieter Sywertszoon and of Gioseffo Zarlino in Venice). Sweelinck's fame as a teacher was very widespread (in Germany he was known as the "maker of organists"), as was his influence. However, the English keyboard school withered during the first half of the 17th century, and the Dutch composers after Sweelinck were either not on his level (Anthoni van Noordt) or left too few compositions to make any significant mark on the history of European music (Pieter Cornet). Sweelinck's influence therefore was primarily important in Germany, Heinrich Scheidemann and Gottfried Scheidt being the first major composers to study under him.

Later northerners like Franz Tunder, Georg Böhm and Johann Adam Reincken all cultivated a harmonically and rhythmically complex improvisatory style rooted in the chorale improvisation tradition. Forms such as the organ prelude (a multi-sectional composition with numerous flourishes and embellishments such as scale runs, arpeggios and complex counterpoint) and the chorale fantasia (a musical setting of a whole verse of the chorale text, resulting in a multi-sectional composition with contrasting sections for different lines) were developed almost exclusively by north German composers. Dieterich Buxtehude's work represents the pinnacle of this tradition; the praeludia form the core of his work. Nikolaus Bruhns was the most important of Buxtehude's pupils, but he died early and only a few works by him survive.

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