Britain: A country named after Celts, populated by Saxons, with a French national motto, and a Latin symbol.

What’s more, the ER “logo” was used before… during the reign of Elizabeth I. Interestingly, in those days, when the Elizabethans were portraying historical figures in theatres such as the Globe theatre, they would act in contemporary dress (in the 16th century people didn’t have the same concept of “historical accuracy” as we do now). So nobles portrayed in a history play would dress as contemporary English nobles of that time, perhaps with a few conventionalized frills added, depending on the character. What I read long ago somewhere was that in a production such as Julius Caesar or Titus Andronicus, any ancient soldiers on stage would have the “ER” symbol on their costumes, much as the Beefeaters still do now.

I’m sorry, I’ll have to invite you to do your own search at the library about the Shakespearean actors (as i mentioned before, the only quote I can do for you is “something I read long ago somewhere”. Of course I tried Google, Britannica online, Wikipedia – no luck.

What I can tell you is that English monarchs have been using Royal Ciphers for a long, long time, and Elizabeth I used “ER”, as Henry VIII used “HR”; it also looks like Edward VI used ER back in those days.

And, appropriate to this thread on British Security Heraldry, I found this nice illustration at the Yeomen of the Guard’s – Beefeaters’ – web site:
http://yeomenoftheguard.com/tunics.JPG

“During the reign of Queen Elizabeth I the ruffs were added, which indeed are worn today. However, in the time of the Stuarts lace and plumed hats took the place of the ruffs and round hats. This history of the English Monarchy, from 1485 to present day, is told by the gold embroidered emblems on the back and front of the tunic. To emphasize the reconciliation of the Houses of York and Lancaster the coats of the Guard bore the Tudor Crown, with the York and Lancaster Roses superimposed below it, and the initials HR (Henry Rex). The initials changed with each succeeding monarch, i.e. ER (for either Edward Rex or Elizabeth Regina), or CR (for Charles Rex), or JR or AR (for James Rex or Anne Regina). The only instance of the King and Queen’s initials being both embroidered on the tunic was during the reign of William III and Mary II (1689-1694/1702) when they appeared entwined WM RR.”
http://yeomenoftheguard.com/#uniform

Also, I just noticed the badge of Anne Boleyn at http://tudorshoppe.com:
It has the badge of Anne Boleyn with her royal cipher, “”AR”” for Anna Regina.