Vienna, he began writing chamber music. His Trio for Violin, Cello and Piano was followed by a Divertimento for Flute and String Trio, and by his first String Quartet, which was the only American prize-winner at the fourth International Concourse for Composition in Monaco. Mechem's premiered his Symphony No. 1 at the 1965 San Francisco Symphony under Josef Krips. Krips commissioned Mechem to write a Second Symphony, which he premiered in 1967. Mechem wrote commissioned choral suites, cantatas and other vocal works during the early 1970s. In the 1970s he saw a performance of Molière's classic satire, Tartuffe, which inspired him to write his first opera. He wrote his own libretto, as he does for all his operas. Premiered in 1980 by the San Francisco Opera, Tartuffe has since played to audiences in Canada, China, Russia, Austria, Germany and Sweden, as well as in the United States. The success of Tartuffe encouraged Mechem to embark upon an opera based on the life of abolitionist, John Brown. An essay Mechem wrote for the American Music Center's online magazine, New Music Box, describes the long evolution of this work. The premiere of John Brown did not take place until 2008. In the twenty-some years between John Brown'''s inception and premiere, Mechem wrote many other compositions, including two new operas: The Rivals, based upon Sheridan's classic play of the same name; and Pride and Prejudice, on Jane Austen's famous novel. "The Rivals" received its professional premiere in September, 2011 by the Skylight Opera Theater, Milwaukee to rave reviews—"A hit, an instant classic". "Pride and Prejudice" was given its concert premiere by the Redwood Symphony in April 2019. Mechem's Songs of The Slave, a suite from John Brown, had its full premiere in 1994 and has enjoyed more than 100 performances. In 1990 Mechem made his first of three trips to Russia, then still the Soviet Union. That year he was a guest of honor at the Tchaikovsky International Competition in Moscow, and was invited back for an all-Mechem symphonic concert by the USSR Radio-Television Orchestra in March 1991, the first time a Soviet orchestra had devoted an entire concert to a living American composer. Five years later he was invited to attend the Russian-language premiere of Tartuffe by the Mussorgsky National Theater for Opera and Ballet in St. Petersburg. Throughout his career Mechem continued to write commissioned choral works. In 2007 the American