The iconic tagline ‘A Diamond Is Forever’ was written by copywriter Frances Gerety at Philadelphia agency NW Ayer in 1947. At the time, De Beers was looking for a campaign that would help boost the sales of diamonds which had fallen during the Great Depression.

Nearly 70 years later, the four-word sentiment has become one of the most recognizable brand slogans of all time. According to a 2013 New York Times article, the tagline has appeared in every De Beers engagement ad since 1948, and is still being used by the brand to this day.

Many have credited Gerety and her counterparts at NW Ayer for essentially inventing the modern concept of an engagement ring, since before the campaign’s debut proposing to a woman with a diamond was not the standard.

These days, you’d be hard-pressed to find someone whose engagement ring doesn’t involve a diamond of sorts, which proves that advertising can have a substantial impact on culture – and can change the way entire generations of men and women view the institution of marriage.

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