Royal Blue was originally a deep blue, darker than the color that we think of today as Royal Blue.
In the 1980s when the original set of named web colors was selected it was the brighter version that was included, and that is the one that we typically call Royal Blue today. This color is known as RoyalBlue in the named HTML colors.
Royal Blue is a popular color choice for flags. The regions below are either using Royal Blue or a color very close.
In 2008 the United States Transportation Security Administration changed their uniform shirts from white to royal blue.