History of the Anthem:
In The Oxford Companion to Music, Percy Scholes points out the similarities to an early plainsong melody, although the rhythm is very distinctly that of a galliard,[10] and he gives examples of several such dance tunes that bear a striking resemblance to "God Save the King". Scholes quotes a keyboard piece by John Bull (1619) which has some similarities to the modern tune, depending on the placing of accidentals which at that time were unwritten in certain cases and left to the discretion of the player (see musica ficta). He also points to several pieces by Henry Purcell, one of which includes the opening notes of the modern tune, setting the words "God Save the King". Nineteenth-century scholars and commentators mention the widespread belief that an old Scots carol, "Remember O Thou Man", was the source of the tune.[11][12]
The first published version that resembles the present tune appeared in 1744 in Thesaurus Musicus. The 1744 version of the song was popularised in Scotland and England the following year, with the landing of Charles Edward Stuart and was published in The Gentleman's Magazine (see illustration above). This manuscript has the tune depart from that which is used today at several points, one as early as the first bar, but is otherwise clearly a strong relative of the contemporary anthem. It was recorded as being sung in London theatres in 1745, with, for example, Thomas Arne writing a setting of the tune for the Drury Lane Theatre.
Scholes' analysis includes mention of "untenable" and "doubtful" claims, as well as "an American misattribution"
