A look back to when De Beers changed the rules of engagement

In 1947, De Beers created a touchstone that changed the entire Western world. It was a campaign that created a new behaviour, one that has subsequently become embedded in the heart of our shared culture.

It is, of course, the "A diamond is forever" campaign, which launched first in the US and then rolled out globally. It single-handedly created the tradition of gifting a diamond ring to your significant other when popping the question.

These days, most people think this is an age-old tradition dating back centuries, when in fact it’s the result of one of the most brilliant ad campaigns in history. Your love is permanent? Then prove it with something that’s equally indestructible.

De Beers even started the myth of the ring needing to cost the equivalent of two months’ salary with the impeccable question, “How else could two months’ salary last forever?”

Before this campaign, it was highly unusual to give the gift of a diamond ring when proposing marriage. In 1940, only 10% of first-time brides were receiving diamond engagement rings; by 1990 that number had skyrocketed to 80%. 

The results are evident: between 1939 and 1979, De Beers’ wholesale diamond sales in the US alone increased from $23m to $2.1bn. The company’s advertising budget increased from $200,000 to $10m a year.

Of course, changing Americans’ social attitudes to embed a belief that their marriage is incomplete without a diamond is one thing, but De Beers had to complement this social manipulation with monopolising the diamond mining market and restricting supply, thus creating scarcity of product. 

This example of effectiveness in creating a consumer ritual is far from unblemished, however. It should be highlighted that De Beers’ supply chain was deeply problematic, with many harms caused by its mining operation, especially in South Africa.

To further establish the diamond gifting tradition, De Beers also pushed the message with its involvement in the 1953 movie Gentlemen Prefer Blondes, getting the iconic Marilyn Monroe to sing the equally iconic Diamonds Are a Girl’s Best Friend, an example of early branded content.

However, while it’s true that perhaps no other brands have the capability to affect an entire global market in this way, there are still so many lessons marketers can learn from what De Beers accomplished.

On the one hand, the importance of a transparent and healthy product supply chain is finally getting the value it deserves. Companies like De Beers, which has since radically evolved its operations, are coming under increasing scrutiny.

On the other, from a communications standpoint, the concept of tying the diamond ring to "two months’ salary" was a masterpiece. It quantified the tangible behaviour the brand was trying to encourage. It combined spending a lot of money with a life event that a huge percentage of consumers will experience.

But perhaps most importantly, De Beers understood that success was tied to culture. The brand identified and seized a cultural moment and was able to completely reinvent how we engage with it.

No surprise that "A diamond is forever" was voted the greatest advertising slogan of the 20th Century, really.

I love this campaign for its beautiful simplicity. I love it for its huge impact on culture and how it managed to change whole generations’ view of the institution of marriage.

Other brands, quite rightly, dream of being able to generate that depth of global behavioural change. I know I do.

Franky Farmer is strategy director at media agency UM.