The "Little Organ Book"--unpretentious title for one monumental
collection--was conceived early in Bach's career as a series of
preludes appropriate for each season of the liturgical calendar.
Bach's grand conception for the cycle is revealed in the titles
of 164 planned chorales with space for each one eventually to be
added. Although never completed, Bach's "little" book does
contain forty-six chorale preludes representing some of the most
beautiful in that genre. They include four chorales for Advent,
thirteen for Christmas and New Year, thirteen for Holy Week and
Easter, and fifteen for other events. Whereas the Orgelbüchlein
was dedicated to "the Prince of Anhalt-Cöthen," most of it was
composed during Bach's prior appointment in Weimar. His official
duty in that city was as organist, and Bach's greatest
compositions for that instrument date from this period. On the
title page of Orgelbüchlein Bach writes, "so that the organ
student might learn how to develop a chorale, in various ways,
and at the same t