He was the best-known composer for the organ in north Germany in the early to mid-17th century, and was an important forerunner of Dieterich Buxtehude and J.S.
His father was an organist in both Wöhrden and Hamburg, and probably Scheidemann received some early instruction from him.
Unlike the other early Baroque German composers, such as Praetorius, Schütz, Scheidt, and Schein, each of whom wrote in most of the current genres and styles, Scheidemann wrote almost entirely organ music.
In addition to his chorale arrangements, he also wrote important arrangements of the Magnificat, which are not only in multiple parts but are in cyclic form towards liturgical use in alternation with the choir during the so-called Vespers, a technique in multiple-movement musical construction which was not to return with vigor until the 19th century.
Among his students were Johann Adam Reincken, his successor at the St. Catharine Church in Hamburg, and (possibly) Dieterich Buxtehude.