Is there a reason that the colour purple is associated with royalty?

Question

Was there some kind of real-world instance or happening we can point to that caused purple to become the “royal colour”?

In: 51

Answer 1

Royal purple used to be the most expensive and difficult ~~die~~ dye to make.

It was made from Murex snails which were hard to find and you needed a significant number of them for a small amount of dye.

Since the dye was expensive it became associated with wealth and royalty