Crossover isn't a new concept. Classical musicians have been straying into the pop world (and pop musicians have been borrowing from their classical brethren) since the early 20th century. With that in mind, here is a brief history of the crossover phenomenon.

1904-1942 Irish-American tenor John McCormack becomes perhaps the first best-selling crossover artist. A performer at the Metropolitan Opera and London's Covent Garden, he also sold millions of recordings of popular ballads and folk songs.
Listen to John McCormack singing "Green Isle of Erin" (1904)

1940s Mario Lanza defines the modern popular tenor, signing a contract with MGM Studios and appearing in Hollywood films like "The Midnight Kiss" and "The Great Caruso." He also hosts his own CBS radio series and has several chart-topping hits.

1950s Liberace, a classical pianist from Milwaukee, becomes a major television personality, bringing kitschy showmanship to classical music in all its rhinestone-gold lame-and-sequined glory.

1952 Violinist Yehudi Menuhin travels to India, studies yoga, and becomes a colleague of sitarist Ravi Shankar. He records an album with Shankar in 1966. Later he collaborates with jazz violinist Stéphane Grappelli.

1969 Hard-rockers Deep Purple collaborate with the Royal Philharmonic Orchestra on "Concerto for Group and Orchestra," an early melding of heavy-metal guitar with more refined strings.

1972 English super-group Emerson, Lake, and Palmer achieve commercial success with their progressive-rock take on Mussorgsky's "Pictures at an Exhibition."
Listen to an excerpt from Emerson, Lake, and Palmer's "Pictures at an Exhibition."(1904)

1975 James Galway gives up his job as principal flutist in the Berlin Philharmonic and kicks off his solo career with “Annie's Song,” an album of folk song arrangements, classical favorites, and transcriptions, including the title song by John Denver.
James Galway talks about his early crossover efforts on Soundcheck Listen to an excerpt here

1980s The term “crossover” begins to be used in the music business, referring to classical musicians who move into the pop world.

1990 The Three Tenors -- Luciano Pavarotti, Placido Domingo and José Carreras -- are formed on the eve of the 1990 FIFA World Cup final in Italy . Their success leads to various imitations, including the Irish Tenors, the Three Canadian Tenors, the Ten Tenors, the Three Sopranos, and the Three Chinese Tenors.

1992 Launch of England's Classic FM, the first national commercial radio station broadcasting classical music in a popular and accessible style. Classic FM also runs a digital TV channel playing classical music videos.

1996 Tenor Andrea Bocelli begins his European chart dominance with the release of "Time to Say Goodbye," a duet with Sarah Brightman.

1998 Charlotte Church, a 12-year-old girl from Wales, explodes onto the classical scene with "Voice of an Angel," an album that goes gold in the US. She appears on Letterman, Leno, Oprah and Rosie.

2000 Creation of Bond, a British string quartet consisting of flamboyant and attractive young women with classical music pedigrees. Considered classical music's response to the Spice Girls, the group favors sex-appeal and even partial nudity. Their album topped the crossover charts in the US and the UK .

2001 Billy Joel ends a nearly decade-long hiatus from writing music with an album of classical piano pieces. Recorded by the British-Korean pianist Richard Joo, it spends 18 weeks on the top of the charts.

2002 Peter Gelb, president of Sony Classical (and now general manager of the Metropolitan Opera) says that he is setting out "to redefine the classical label . . . to return to the idea of classical music as an emotional experience for the listener."

2003 Christopher O'Riley releases “True Love Waits,” the music of Radiohead re-imagined for solo piano.
Listen to Christopher O'Riley's Live Performance on Soundcheck

2006 Il Divo, an operatic pop vocal group created by Simon Cowell, releases "Ancora," which enters Billboard's album chart at number one, selling more than 150,000 copies during its first week of sales. The group later performs at the 2006 FIFA World Cup.

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What do you think of crossover? Does it bring new audiences to classical? Does it cheapen a proud tradition?
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WNYC's Soundcheck covers crossover:

New York Times classical music critic Anne Midgette discusses the number-one album by the operatic boy band Il Divo
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Chart-topping English soprano and actress Sarah Brightman talks about her crossover career
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British cultural critic Norman Lebrecht explains why "the year 2004 will be the last for the classical record industry" and why he feels that crossover is part of the problem.
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