Princess Diana's engagement ring was actually inspired by this other royal

It's safe to say that Princess Diana's engagement ring is perhaps one of the most famous in the world. We all know it now sits on Kate Middleton's finger, and is worth a fortune.

At the time, the choice of engagement ring caused controversy, as instead of choosing a style from the royal collection (and we can all imagine how fabulous that collection is), Diana chose from a catalogue. A posh one, don't worry.

This is something we get a glimpse of in the new season of The Crown. In episode three, we see a young Diana sit with Prince Charles in a room with a tray of rings to choose from, including some from the Queen as well as some Garrard (the official Crown Jeweller) options.

She opts for one of the flashiest rings, a large oval sapphire surrounded by diamonds, which she later had re-designed to her liking. The Queen was said to be unimpressed with how flashy it was. Diana also mentioned she liked the fact that it matched her eyes.

But perhaps she would've been happy to hear that the ring was actually designed as a nod to another, older, royal.

Called the Marguerite ring, it was actually inspired by a brooch that Prince Albert commissioned Garrard to make in 1840 for Queen Victoria.

So although it might have been a new model, it had some historical value.