Claim: Peter Cetera was on an album.

Chicago is an American rock band formed in 1967 in Chicago , Illinois . The self-described `` rock and roll band with horns '' began as a politically charged , sometimes experimental , rock band and later moved to a predominantly softer sound , generating several hit ballads . The group had a steady stream of hits throughout the 1970s and 1980s . Since at least 2008 , Billboard has shown Chicago to be the `` greatest of all time '' American band in singles chart success , and since 2015 , the `` greatest of all time '' American band in album chart success as well . Chicago is one of the longest-running and most successful rock groups , and one of the world 's best-selling groups of all time , having sold more than 100 million records .   According to Billboard , Chicago was the leading U.S. singles charting group during the 1970s . They have sold over 40 million units in the U.S. , with 23 gold , 18 platinum , and 8 multi-platinum albums . Over the course of their career they have had five number-one albums and 21 top-ten singles . They were inducted into the Rock and Roll Hall of Fame on April 8 , 2016 at Barclays Center in Brooklyn , New York . Original band members Peter Cetera , Robert Lamm , and James Pankow are among the 2017 Songwriters Hall of Fame inductees for their songwriting efforts as members of the music group , Chicago .