Hassler was very influential in his day both Bach (O Haput voll Blut und Wunde) and Schütz (Psalmen Davids) quoted his music. The son of a stonecutter and part time musician in Nuremburg he was sent to Venice to study music and composition. In Venice he came under the influence of the Gabrieli's studying under Andrea Gabrieli he stayed in Venice for eighteen months and returned to Germany taking up a position in Augsburg as chamber organist to Octavian Fugger II. Word of this talented musician and composer spread the Landgrave of Hesse tried to "poach" him from the Fuggers while the emperor granted him a potentially very lucrative patent to copyright his works. When Fugger died in 1600 the town council tried to keep him in Augsburg by making him the town's musical director but Hassler returned to his home town a year later to take up a similar posting, in 1607 he travelled to Ulm where he married severing all ties to Nuremburg. In 1608 Christian II of Saxony commissioned a composition from him and then appointed Hassler to his staff, he continued as a member of the Saxon court rising quickly to Kapellmeister until his death in 1612.
Musically Hassler was both conservative and ecumenical, ecumenical in that although he himself was a protestant he was quite happy to compose for both the Catholic and Lutheran churches and conservative in that he never wrote a piece that used that hallmark of baroque music the basso continuo confining his religious compositions to the polyphonic idiom that had been at its height fifty years earlier not only that but you'll often hear the cantus firmus as a motif in every part of his composition. Having said that he was musically conservative I had better qualify that statement somewhat by saying that it was his religious music that was so conservative, he wrote a considerable quantity of secular music such as madrigals, instrumental works, and dance songs, in all of which genres he allowed himself to be somewhat more free-handed. His motet Ad Dominum cum tribularer (In my distress I cried unto the Lord) which takes its texts from the opening verses of Psalm 120 is another exception to the conservatism rule. It's very chromatic with none of the traditional diatonic harmonies, and as you listen you can hear what he was trying to do – to make his music match the text to portray both tribulation (cum tribularer) and its cause a deceitful tongue (lingua dolosa).