‘Galla-Tage’ lists and reports of courtly activities published in the calendars have frequently been used as primary sources—relating the composition of secular music for birth- and name-days of the ruling family (including works written by Bach for performance during visits of the Dresden court to Leipzig) and to explaining the style, length, and orchestration of certain liturgical works composed for the Dresden Catholic court church.
Nevertheless, little or no reference has been made to the monthly calendars
appearing at the opening of each edition—the closely related ‘Verbessert.’
(Lutheran) and Gregorian (Catholic) calendars, and the Julian calendar.
These represent resources of importance to understanding the annual cycles
of Dresden society—Lutheran and Catholic—and the place of liturgical music
within that society. The Gregorian calendars demonstrates that plenary
indulgences had been re-introduced into Saxony; they illuminate the role
of court composers and musicians in the confessional displays by the Royal
Polish and Saxon Electoral court; they reveal more fully the use of music
in the proselytizing activities of the Dresden Jesuits. Moreover, the purpose
of many musical works composed for the Dresden Catholic court church during
the era of Heinichen, Ristori, Zelenka, and Hasse is more clearly defined.