Scheidemann was instrumental in establishing the north German organ school. He was a student of Sweelinck in Amsterdam from 1611-1614 later succeeding his father as organist of the Catharinenkirche in Hamburg (c.1625-1629). He served in this position until his own death. Among Scheidemann's compositions are collaborations with Thomas Selle, Praetorius, and Weckmann. He himself helped to increase the organ at the Catharinen to four manuals and pedals with fifty six stops. This is evidence not of his excellent playing skills as an organist but of his expertise in organ construction. Scheidemann was also known for his superiority as a teacher. Approximately fifty of his organ works are extant bringing Sweelinck's keyboard method out through the organ. Compositions included chorales and Magnificat settings. The chorale settings are noted for their significance in the development of the fantasia and the "praeambula" anxiously anticipate the prelude and fugue. His most important composition is the "Tocatta in G" influenced by both Sweelinck's structures and the north German treatment of the organ with more than one manual. ~ Keith Johnson, Rovi