Italian composer, possibly a pupil of Costanzo Porta. Became a Franciscan monk in 1596; in 1593-7 directed music at Mantua cathedral, and was probably still working in that city in1600. His next recorded post was as choirmaster in Fano (1610-12); he later visited Venice and finally returned to Mantua. Viadana was a prolific church composer, publishing no fewer than 22 volumes of motets, psalm collections, etc.; he also wrote four books of madrigals and canzonets and one of instrumental sinfonie. His historical importance liesin the fact that he established the small-scale concertato style and the use of the continuo in church music with his epoch-making Cento concerti ecclesiastici of 1602 (two further volumes appeared later). In writing for between one and four voices with indispensable organ accompaniment, he proved that the new medium was feasible for church music, and though the musical results were often modest or even backward-looking, the influence of the collection was immense. The preface contains important information on the new art of continuo playing. Some of the motets do show the chromatic or true monodic or duet writing of the stile moderno, and illustrate neatly-conceived formal structures.