Step 1 : Introduction to the question "Before achieving fame as Sonny and Cher, the iconic pop duo performed under what stage name?"
...Before achieving international fame as Sonny and Cher, Sonny Bono and Cherilyn Sarkisian performed under the stage names Caesar and Cleo in the early 1960s. The duo released several unsuccessful singles under that name before reinventing themselves as Sonny and Cher in 1964. Their breakthrough came in 1965 with the chart-topping hit "I Got You Babe," which reached No. 1 on both the American and British charts. Their distinctive harmonies, unconventional fashion, and playful chemistry made them one of the decade's most recognizable musical acts.