About Dario Castello and Giovanni Battista Fontana, two Italian composers from the turn of the 17th century, musical scholarship hasn’t much to tell us. We know as little about Castello, who was leading an ensemble at St. Mark’s around 1629, as we do about the exact birth and death dates of Fontana, who came from Brescia and probably perished during the 1630 outbreak of plague in Padua. Yet there are a number of surviving works by both men that reveal them to have been remarkable composers for the violin. Two books by Castello of sonate concertate in one to four parts, in stil moderno with continuo, were printed during the composer’s lifetime. In his new recording violinist John Holloway has selected a number of sonatas from this collection to couple with similar works by Fontana, some originally for violin as well as some conceived for other string or wind instruments. Along with solo violin sonatas, Holloway has chosen six of these sonatas for violin and basso continuo that can be regarded as precursors of the later trio sonata or even as early examples of that genre. They also serve as proof that there is still undiscovered territory on the early music map.