What we have here is a hit song that started as a Coke commercial, sung by the group commissioned to sing the jingle. At first, it was a radio spot called "I'd Like To Buy The World A Coke," a slogan written by William Backer who worked for Coke's ad agency, McCann-Erickson. Backer had a track record of success, having created the "Things Go Better with Coke" and "The Real Thing" campaigns for Coke. The idea for this one was Coke bringing people together in harmony - it was actually part of "The Real Thing" campaign, with the line, "That's the real thing," inserted into the lyric.
The commercial was sung by a British group called The New Seekers, whose biggest hit to that point was a cover of Melanie's "What Have They Done to My Song, Ma
" that reached #14 US. The commercial started running on radio stations on February 12, 1971; it was so catchy listeners requested it like they would a song. Backer and his team knew they had a winner, so they commissioned a television commercial using the jingle, which became the iconic "Hilltop" commercial
showing a group of children from various countries singing the song together outside of Rome. The TV spot started airing in July and proved very popular, boosting sales of Coke and imbuing it with an aura of goodwill and harmony. The New Seekers recorded a full version of the song as "I'd Like To Teach The World To Sing (In Perfect Harmony)" with references to Coke removed so radio stations could play it as a song. It rose up the chart, reaching #7 on January 15, 1972.