The root cause of Francesco Cavalli's importance in the history of opera lies, I believe, in the fact that he was the first composer to write almost exclusively for the professional public theatre. That he did so with outstanding success for twenty-seven years, enhancing the reputation and consolidating the supremacy of Venetian opera throughout Europe, is a testimony to the sheer quality of his music and theatrical ability which, of course, must count for more than anything else in a final assessment.