He was born in Luzzara, Reggio Emilia, to Francesco and Flaminia and was baptized there on March 1, 1616. We know nothing about his musical education, nor is it known where he completed his seminary studies to obtain his ordination as a priest. In 1641, when he published his first work, he declared himself organist and choirmaster of the Basilica of S. Andrea in Mantua; shortly after, in 1647-48, he was listed as master of chamber music for the Duke of Sabbioneta and Bozzolo. At the end of 1648, he was appointed choirmaster of the Accademia della Morte in Ferrara, where he remained until 1652, to take up the same position at S. Maria Maggiore in Bergamo; he remained there until April 25, 1657, to return to Ferrara for only a few months, since on August 31, 1657, he was elected choirmaster at S. Petronio in Bologna.
During this last assignment, the longest of his career (lasting fourteen years), he carried out an intense creative activity, publishing numerous compositions (from op. XIX to LVIII) and profoundly influencing the structure and activity of the Petronian chapel; shortly after his election he obtained to take upon himself the choice of the vice-master and at the same time had all the members of the chapel dismissed (except for the two organists); seven days later he had it established that the palace musicians should no longer be borrowed, due to their bad habit of abandoning the functions in the basilica early. At the beginning of the following year, the chapters to be observed having been established, on January 16, 1658, the musicians were gradually rehired, evidently according to a selection and a program desired by Cazzati, to arrive on September 6. 1658, to the definitive reorganization of the chapel, whose staff was set at four sopranos, six contraltos, six tenors, six basses, two violins, two alto-violas, two tenor-violas, two trombones, a violoncello, a contrabasso violone grosso, a theorbo, two organists.
Particularly significant of the impetus brought by Cazzati to the activity of the chapel is the exceptional increase undergone by the musical preparation for the annual patronal feast of S. Petronio (October 4): before his arrival, the participation of foreign or extraordinary musicians ranged in number from ten to twenty with an expense usually less than fifty lire; already in 1657, therefore a few months after the appointment, these temporary performers amount to twenty-four for the cost of 109 lire, but in 1658 they become sixty-eight (for 756.15 lire), while in the two following years the expense grows out of all proportion, motivated in large part by the engagement of soloists and related travel, food and lodging expenses. From 1661 and until the end of his mandate, the cost will remain approximately within the limits reached in 1658.
Having requested and obtained permission on June 27, 1671, from the vestries of the Bolognese basilica, Cazzati returned to Mantua to assume the direction of the chapel and chamber music of Duchess Anna Isabella; in this office, he ended his existence at the end of September 1678 (as is evident from the letter of his executor, Giovanni Furlani, to the vestries of S. Petronio dated January 20, 1679, in which he communicated the legacy to the same basilica of "twelve large leather books to Palestrina").
It cannot be said that the figure of Cazzati has so far met with much favor among scholars of the Baroque era's musical history. The main difficulty in achieving a sufficient overall vision of his work undoubtedly lies, on the one hand, in the truly unusual quantity and, on the other, in the great variety of genres, forms, and sound structures. And if the great quantity usually predisposes unfavorably for a qualitative judgment, on the work of Cazzati, the echo of the unfortunate polemic raised against him by Giulio Cesare Arresti seems to weigh even more. It would, however, be desirable to see an accurate study undertaken soon on this musician, whose undoubted historical importance - especially about the Bolognese school - has already been intuited by more than one historian.