Most famous, perhaps, for the beautiful soprano solo ‘Laudate Dominum’, Mozart’s Vespers K.399 were composed for liturgical use in Salzburg Cathedral in 1780.
The work is divided into six movements, each a setting of a Psalm concluding with the doxology (Gloria Patri), the whole intended for use at the sunset evening prayer service known as Vespers.
The piece was commissioned by the Archbishop of Saltzburg, Hieronymus von Colloredo, who appears to have appreciated and tolerated Mozart in equal measure, eventually dismissing him in frustration and allowing his chamberlain to inflict a severe kicking on the way out.Colloredo
It is hard to believe that a musician such as Mozart was not treasured by his employers. Yet Colloredo was not unusual for his time: it is reported that when Archduke Ferdinand of Austria asked his mother whether he should employ Mozart at court, she replied
“You asked me about taking into your service, the young Salzburger. I cannot think what as, for I do not believe that you have any need of a composer or of useless persons. But if it would give you pleasure I will not prevent you. What I say is do not burden yourself with useless persons, and the claims of such persons on your service”.
For an amusing account of Mozart’s relationship with his employers, see here