This chart (public domain from Wikimedia Commons) illustrates the question. Is there an explanation for why the Union Jack have a darker shade of blue than the original Scottish flag that it's based on?

Union Jag evolution

  • 13
    This is covered by the wikipedia article on the Flag of Scotland i.e. "In the case of the Saltire, variations in shades of blue have resulted in the background of the flag ranging from sky blue to navy blue."
    – Steve Bird
    Commented Mar 20, 2017 at 19:06
  • 14
    Important to note that per the linked article, it was only formalised in 2003. I grew up in Scotland with a lot of dark blue ones around, and it's still the one I'd personally think of as the 'normal' shade... Commented Mar 20, 2017 at 20:15

1 Answer 1


In 1606, people didn't have pantone guidelines to keep colours consistent - nor did it matter. Heraldry only has a limited number of colors. Variations on blue exist but are not standard, so any blue could be used.

It just so happened that the English were already using a blue, in the Blue Ensign being used by English ships. Wikipedia even suggests its darker colour was more durable:

Various shades of blue have been used in the saltire over the years. The ground of the current Union Flag is a deep "navy" blue (Pantone 280), which can be traced to the colour used for the Blue Ensign of the Royal Navy's historic "Blue Squadron". (Dark shades of colour were used on maritime flags on the basis of durability.)

Adapting the colours of the naval ensign made sense because the Union Jack was originally meant for naval use only. See the original decree:

Whereas, some differences hath arisen between Our subjects of South and North Britaine travelling by Seas, about the bearing of their Flagges...

  • 24
    It's not about pantone guidelines or quality of dye. Heraldry has never put importance on colour tones, and a light blue is considered the same as a marine blue, deep blue, or any over blue shades. You can even use hatching ( en.wikipedia.org/wiki/Hatching_(heraldry) ) and the meaning will stay the same. So, you can put any kind of red and blue on this flag and it will still be the Scottish/English/Irish/UK flag.
    – Shautieh
    Commented Mar 21, 2017 at 5:08
  • 5
    Is it about durability (the dye is particularly hard-wearing), or is it that starting with dark blue means that it's still recognisably blue, even once faded by the weather? Commented Mar 21, 2017 at 9:32
  • 1
    @Shautieh I've edited the answer to account for the heraldry issue.
    – SPavel
    Commented Mar 21, 2017 at 18:26
  • 1
    @CsBalazsHungary Even more accurately, azure was just azure. en.wikipedia.org/wiki/Blazon#Tinctures
    – dbmag9
    Commented Mar 22, 2017 at 8:35
  • 1
    @Shautieh Thanks to you I just learned about hatching in heraldry and I sudder at the thought of redacting and spreading Reinessance's RFCs to set the standards. (:
    – xDaizu
    Commented Mar 22, 2017 at 10:09

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.