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

Must be before they figured out mixing red and blue makes purple. Although that seems so obvious there must be a reason they couldn’t do it

Answer 2

purple dye was originally very expensive to make. it was so expensive that only royalty could afford it.

Answer 3

If my old teacher wasn’t bullshitting me, the dye that was used for the colour purple wouldn’t get bleached out over time and would instead get deeper and richer with age.

Also as other redditors pointed out, that specific purple dye was mad expensive.