Johann Zach (1713-1773) is counted among the most important composers of the so-called pre-classical era. In the 1730s he worked as an organist at various Prague churches and, like many of his fellow composers, left his Bohemian homeland. From 1745 till 1756 he worked in Mainz as court music director, where he possibly composed the present Missa pastorella. In the last nearly 20 years of his life he travelled without any permanent employment to residences and monasteries in the German Empire and Italy. Zach's Pastoral Mass is an exceedingly original and unconventional contribution to a genre that flourished in the second half of the 18th century. This work unites Zach's idiosyncratic personal style, characterized by surprising harmonic progressions and strong rhythmic sophistication, with typical pastoral elements that evoke the Christmas spirit.