Giovanni Battista Fontana is known to history for one only publication, which appears to be a posthumous collection hastily assembled from manuscript sources. It comprises six sonatas for violin and bass and six more for two violins and bass. The publication states that he was from Brescia and worked in various cities in Italy, but nothing else is known about him. The collection was published in 1641 and the 12 sonatas are among the earliest in that form and are considered important for that reason. The music is quite polyphonic in conception, with even the bass line acting more as a separate individual voice than as a true foundational bass. The sonatas are titled so that they may be performed by violin, coronet, bassoon, chitarrone, cello, or similar different instruments.