Giovanni Gabrieli’s last and most important post was that of organist at San. Marco, Venice, following his appointment in 1585 he embarked on a prolific composing schedule for the great Venetian festivals of church and state for the first twenty years he had lavish resources available to him, his compositions for «cori spezzati» – multiple choirs spaced apart, date from this period. However in 1605 Doge Grimani died and there were cutbacks in San Marco's musical establishment. I believe that 'Jubilate Deo' ('O be joyful in the Lord') dates from this second period.The strongest evidence for this lies in the nature of the piece. Gabrieli wrote it for a single choir in style that's clearly influenced by chansons and madrigals. Furthermore it didn't appear in print until after shortly Gabrieli died at which point it was published in no less than three separate collections in Germany. (Gabrieli was far more highly thought of in Germany than he was in Italy).