Well, yes; but since it appears that the term "Maries" for ladies-in-waiting derived specifically from the remarkable fact of Queen Mary's having had four ladies-in-waiting who were all called Mary, that doesn't really get us all that far; though it might be, since those ladies-in-waiting were all famously called Mary, that a fictional addition to the group (or a real character introduced from elsewhere) might automatically be given that name.

Since this thread has returned from the dust of yesteryear, perhaps I should clear up one or two points which were left hanging and may mislead the unwary.

Barry Finn stated that the ballad had been found prior to 1718, subsequently quoting a statement made in the Viking Book of Folk Ballads to a "troublesome fact that some form of the ballad seems to have circulated in Scotland before 1719". The editor, Albert Friedmann, cited no authority for this statement. It may be based in part on a misunderstanding of a comment made by John Knox in his History of the Reformation, and quoted by Child (III 382, footnote; and above, in a slightly different form). Having commented upon the case of one of Queen Mary's ladies of the bedchamber, a Frenchwoman who became pregnant by the queen's apothecary and was condemned for infanticide, Knox continued:

"But not yet was the court purged of whores and whoredom, which was the fountain of such enormities; for it was well known that shame hasted marriage betwix John Semple, called the Dancer, and Mary Livingston, surnamed the Lusty. What bruit the Maries and the rest of the dancers of the court had, the ballads of that age did witness, which for modesty's sake we omit."

The scandal involving an anonymous French lady of the bedchamber and the lesser scandal involving Marie Livingston were entirely separate. There is no evidence that the ballads referred to by Knox were in any way related to the ballad of Mary Hamilton: Child himself commented: "As to the 'ballads' about the Maries mentioned by Knox, I conceive that these may mean nothing more than verses of any sort to the discredit of these ladies." (Child V, 299, footnote).

Lesley Nelson's comment at The Four Marys (referred to above) that "There is speculation that the "apothecary" was Lord Darnley in disguise" is also puzzling. She quotes no source for the anecdote, but since the event took place in 1563 and Darnley did not come to Scotland until 1565, it is worth mentioning only in case someone should unwisely attach any credence to it; particularly as the guilty apothecary, and the Frenchwoman, were both hanged in 1563. (Child, V, 298). Presumably Lesley's reference to "Other versions of this ballad (circa 1563)" are based on Friedmann's (seemingly baseless) speculation.

Child did revise, to an extent, his initial thought that an origin in the Russian incident was the only tenable basis for the ballad. This was in the light of two factors. The first was the discovery of a version (his example U: Child IV 509) which contains the lines

My love he was a pottinger,
Mony drink he gae me,
And a' to put back that bonnie babe,
But alas! it wad na do.

This from a text of 16 stanzas communicated to Walter Scott, 7th January, 1804, by Rev George Paxton, Kilmaurs, near Kilmarnock, Ayrshire (afterwards professor of divinity at Edinburgh); from the mouth of Jean Milne, his "aged mother, formerly an unwearied singer of Scottish songs." The mention of a "pottinger" (apothecary) suggested that there may after all have been a connection with the incident of 1563; what it did not prove was that the ballad is of that period.

The other factor was an article by Andrew Lang in Blackwood's Magazine (September 1895, p. 381 ff.) Lang and Child both felt it unlikely that "a ballad, older and superior in style to anything which we can show to have been produced in the 18th, or even the 17th century, should have been composed after 1719" (the date of the Russian incident involving a Mary Hamilton), and Lang's argument persuaded Child that his earlier, reluctant feeling that the Russian incident had to be the root was now more improbable than the alternative (though also still improbable) explanation; but this is "gut feeling", not firm evidence, and Child reached no firm conclusion (though Joe F implied otherwise earlier on) but left the matter open. This may be the other root of Friedmann's assertion.

All this is scarcely news; everything I have said here was known a century ago, and has been available all along to anybody with a set of Child or access to a decent public library. Nevertheless, things like this have to be repeated from time to time, because so few people read appendices or footnotes; and because so many prefer fakelore to what might actually be true. And we don't know what the truth is here, of course; perhaps the Russian incident involving a Mary Hamilton is just a coincidence, and perhaps it isn't. If we are to look for an answer solely to the time of Queen Mary, however, then the unfortunate heroine was probably not a Hamilton, nor even a Mary; but a Frenchwoman whose name we do not know, far from home and doomed by tragic circumstance.

For little did father or mother wit,
The day they cradled me,
What foreign lands I should travel in,
Or what death I should die.

Child IV 507-8 (version S)