Five-hundred years ago this year, in 1516, King Henry VIII established the role of Master of the Posts, who had responsibility for delivering the royal messages between courts and castles. In 1603, when James VI of Scotland became James I of England, one of his first acts on moving from Edinburgh to London was to extend and develop the postal service to ensure that contact between London and Edinburgh was well maintained.
In 1635 this royal mail service became publicly accessible, with postage payable by the recipient of a letter - it was free to send it, but cost money to receive it! In 1660, Charles II officially launched the General Post Office, and the national postal service was officially born.
Today, half a millennium after the original service, the Royal Mail continues to deliver the bulk of the public post in the UK - the Post Office itself is a separate company which operates as a retail outlet. So in effect, you pay the Post Office for the stamp on your letter, but it's the Royal Mail which is responsible for carrying and delivering it.
Traditionally, public mail boxes served by the Royal Mail bore the insignia of the monarch on the throne when they were established. The first pillar boxes were set up during the reign of Queen Victoria in the 1850s, and bear her royal insignia - VR for Victoria regina.
Around Edinburgh you'll find many VR postboxes (pre-1901), an occasional Edward VII (1901-1910), and plenty of GR boxes, from the reigns of George V and George VI. What you won't find, however, are boxes bearing the insignia of Elizabeth II, our current monarch.
During the 1970s, a number of postboxes bearing the EIIR emblem were vandalised and were targets of explosive devices left in the boxes, which caused considerable risk to the members of the postal service responsible for making collections from them.
The resistance that some people in Scotland had to the EIIR insignia was based on the assertion that Elizabeth II of England is only (technically) Elizabeth I of Scotland - Elizabeth I of England ruled before Scotland and England were united. As such, some people in Scotland felt that the EIIR insignia was not appropriate for the monarch they failed to recognise by that title.
With such explosive resistance proving a threat to mail service employees, an agreement was reached that post boxes in Scotland would not bear the insignia of Elizabeth II, but would instead be marked simply with a general royal emblem or a crown crest.
So next time you drop off some postcards home in one of our distinctive red post boxes around the city, check out the emblem to find out which monarch was on the throne when that particular post box was established!
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Edinburgh Expert is run by Gareth Davies, an adopted native of Edinburgh with 18 years of experience living and working in the city.