Information about legend: GEORGIVS VI D : G : BR : OMN : REX FIDEI DEF.

Translated from Latin: George the Sixth, by the Grace of God, King of all the Britains, Defender of the Faith.

The "BR OMN" part is sometimes translated as "of all the Britons" (people), similar to how earlier monarchs were styled kings "of the English"; however, this can only be said of a title like "BRIT REX" - King of the British - which implies "all the British".

In 1868, a book by C. W. Dilke popularised the phrase "Greater Britain" to mean Britain and all its colonies. This may have led to the proposal of the title "King of all Britains", in the last years of the 19th century, by the Earl of Rosebery. The Oxford English Dictionary provides two quotes:

1897 Earl of Rosebery in Daily News 5 July 4/5 : "`Regina Britanniarum' - the Queen of the Britains... She is sovereign, not of one or two, but of numberless Britains, all self-supporting."
1901 Westminster Gazette 11 Dec. 2/2: "Lord Rosebery has succeeded with his cry of "All the Britains", as the three letters "Omn" on the new coins are to testify... Our King henceforth is to be King of All the Britains."

This style may have been influenced by the Russian style of "Czar of all the Russias". It appeared on coins abbreviated as Britt. Omn.: the double T in Britt is a mark of plural, a common abbreviation on Roman coins.