Dario Castello was a minor though significant figure on the music scene in seventeenth century Italy. He published two collections of sonatas made up of 29 works, scored for four instruments (or fewer) and continuo. He was also a prominent chamber musician in his day, having connections with Claudio Monteverdi. Little is known about Castello's life; even information on his vital dates is scant and varies widely. He was born probably in the late-sixteenth century in Venice, the city where virtually all his recorded musical activity was centered. It is known from information in his publications that by 1621 he was a musician at San Marco Church in Venice and performed regularly in his own wind ensemble. Since Monteverdi was maestro di cappella at San Marco during Castello's period of service, it is not surprising that Castello's music shows the influence of this great Italian master, particularly in the use of the so-called stile concitata. Castello's music also divulged other characteristics typical of the day, notably the deft use of contrasting tempos and other colorful features associated with the stile moderno. His works were typically scored for sackbuts, cornetti, violins, and dulcians. It seems Castello may have had other relatives who were musicians, since there were several Castellos listed as musicians at San Marco in the seventeenth century. One possible relative was Giovanni Battista Castello (not the Renaissance-era painter and sculptor), who was active in the 1620s in the service of the Doge of Venice. Some believe that Dario Castello died in the 1630 plague that ravaged Venice. Others conjecture he lived on until the 1650s. A reprinted edition of his sonatas from 1658 suggests in a note that he was no longer alive.