When Lady Diana Spencer married Prince Charles on July 29, 1981, the world waited anxiously to see what would become one of the most famous wedding dresses of all time.

Just 19 years old, Diana had become a fashion icon overnight after the couple's engagement was announced – and fever surrounding the wedding and what the future Princess would wear took Britain (and the world) by storm.

While their marriage was not to last, the image of Diana's extravagant puff-sleeve wedding dress has stuck with royal fans for decades.

Here, we take a look back at the Princess of Wales' wedding dress – and some little-known facts about the iconic look.

Her clothing designers initially thought the job application was a joke

While many expected Diana to choose a more established British fashion house for her big day, the young husband-and-wife team – David and Elizabeth Emanuel were ultimately chosen to design her dress – and the pair actually thought they were joking at first.

Although the couple had made several outfits for the bride-to-be in the run-up to the wedding, they never expected to design for one of the biggest royal events in history.

Diana's dress wasn't white – and for good reason

With huge puffy sleeves, bows, lace and 10,000 pearls, the silk taffeta gown inspired bridal trends throughout the 1980s – and endless copies were distributed so eager brides could get the look.

As for the classy, ​​tousled silhouette, she told the publication that "inspiration came from everywhere."

The ivory shade of the dress "was so flattering for her English rose color," Elizabeth Emanuel told the Daily Mail.

“I find that white lace tends to look cheap.

The ivory added to Diana's natural beauty."

The veil was the longest in royal history

The Emanuels set out to make a splash when it came to Diana's dress, and they certainly succeeded – the 7.6 meter veil is the longest of any royal wedding dress in history.

While researching royal wedding dresses, the couple "found out that the biggest royal veil was six metres", David told Today - so they decided to make one even longer.

The designers were "horrified" about the dress's wrinkles

One of the aspects of Diana's dress that is often criticized is how wrinkled she looked on her wedding day.

Speaking during a 2018 ITV special called 'Invitation to the Royal Wedding', Elizabeth said (via The Mirror) that the pair thought she would 'wrinkle a bit', but not to the extent that she was while Diana was traveling to the church.

"I was horrified, really, because it was so wrinkled.

It was much more than we thought."

There was a spare dress that no one knew about

When it came to dressing Diana, they weren't taking any chances – so they created a second, different dress for each occasion.

As Elizabeth told the Daily Mail, the backup style was similar to Princess Di's original, but a little simpler;

it lacked all the lace trim and had a shorter sleeve and different bodice.

Diana stained her dress with perfume just before the wedding

According to Peopl, 'Lady Di' chose Quelques Fleurs, a romantic scent from Parisian perfumer Houbigant, for her big day.

However, the perfume - which takes "more than 15,000 flowers" to create a bottle, according to the brand - ended up all over Diana's dress just minutes before she stepped out.

Although Elizabeth Emanuel told the Daily Mail that they created an extra skirt that could have been attached to the dress "just in case she spilled something down that day," it turns out there wasn't enough time for that.