The New Seekers
Coke Commercial @ 1971
Coke Commerical @ Christmas, 1978
"I'd Like to Teach the World to Sing (In Perfect Harmony)" was originated as a jingle for Coca Cola's commercial, "Hilltop" in 1971. The jingle was produced by Billy Davis, and performed by The New Seekers. Of course, the jingle was so popular at the time.
Dropped the reference to Coca Cola (I'd like to buy the world a Coke), the full-length song was re-recorded by The New Seekers, and the Hillside Singers in 1973 respectively.
The version by the New Seekers reached #7 in the United States. In the meantime, the Hillside Singers' version was also a successful (as a single) in the same year. It reached #13 on the Billboard Hot 100, and #5 on Billboard's Adult Contemporary Chart.
source: wikipedia, library of congress