Born in Parma, Campanini studied music at that city's conservatory, making his debut with a performance of Carmen, also in Parma, in 1883. That year he was invited to New York City during the inaugural season of the Metropolitan Opera, and was offered a position as assistant conductor with the company. Five years later he returned to the United States to lead the American premiere of Giuseppe Verdi's Otello at the Academy of Music. Desdemona was sung by Eva Tetrazzini, who Campanini had married in 1887.
He conducted at São Carlos, Lisbon, from 1888 to 1903 on some of the opera seasons, where he conducted, among others, the premiere of Augusto Machado's "Mario Wetter" (1898) and Alfredo Keil's "A Serrana" (1899) (considered the best Portuguese opera), with Eva Tetrazzini in the leading roles. Campanini conducted at La Scala for three years, where he conducted the premiere of Puccini's Madama Butterfly in 1904. In 1906 he was appointed artistic director of the newly formed Manhattan Opera Company. He stayed there for three years before resigning over artistic disagreements with the company's manager, Oscar Hammerstein I. In 1910 he became the first conductor of the Chicago Opera, remaining there until his death; he brought the company with him in 1918 to New York for a four-week season that included Amelita Galli-Curci's first appearance in the city. He was initiated as an honorary member of Phi Mu Alpha Sinfonia Fraternity in 1917. From 1915 to his death in 1919, Campanini was artistic director and principal conductor of the Chicago Opera Association.
Campanini was known for his association with French opera, and introduced numerous works to the United States; these included Hérodiade, I gioielli della Madonna, Louise, Pelléas et Mélisande, Monna Vanna, Jules Massenet's Sapho, and Thaïs. Campanini died in Chicago in 1919.
- Francisco Fonseca Benevides, "O Real Thetro de S. Carlos de Lisboa 1883 -1902". Lisbon; Typographia e Lithografia de Ricardo Souza & Salles, 1902
- David Ewen, Encyclopedia of the Opera: New Enlarged Edition. New York; Hill and Wang, 1963.
- Verdi in Portugal: Cleofonte Campanini*
- Media related to Cleofonte Campanini at Wikimedia Commons