A manuscript pedigree of uncertain origin is reported to have stated that Robert Swift married Agnes Anne, a daughter of Martin Anne of Frickley.[1] On the one hand, this is a rather shaky source to rely on, but on the other hand there really was a Martin Anne of Frickley who was exactly the right age to be her father, and this seems like a rather unlikely target for forgery, so there does not seem to be any particular reason to doubt the statement. The main reason this information seems to have filtered down to us is that she was apparently an ancestor of Jonathan Swift, and this turned up in the research of his pedigree.
Her birth date is unknown, and is simply estimated to be around 1460. It could credibly by somewhat earlier or later.
Note
Note: Is Surname really Anne? Should surname be Unknown or another name?
Yep, it's Anne.
Robert Swyfte, Esq. of Allergill, and of Rotherham, co. York. This Robert m. twice: 1st, a dau. of William Hansarde, Esq. of Walworth, by which lady he had issue, of whom presently; and 2ndly, Agnes, dau. of Martin Anne, Esq. of Frickley, by whom he had two sons[2]
Sources
↑ William Monck Mason, The History and Antiquities of the Collegiate and Cathedral Church of St. Patrick, Near Dublin, from Its Foundation in 1190 to the Year 1819 ... Collected, Chefly, from Sources of Orginal Record, Dublin, 1820, p. 225 Google Books
↑ A Genealogical and Heraldic History of the Landed Gentry of Great Britain & Ireland p. 1345
Glover, Robert. The visitation of Yorkshire, made in the years 1584/5. 1875. Pg. 576. Archive.org. [1]