Albert J. Beveridge,
The Life of John Marshall, Volume 1…
“ Sir William Marshall, regent of the kingdom of England and restorer of Magna Charta; a Captain John Marshall, who distinguished himself at the siege of Calais in 1558; and finally, the Irish captain who fought Cromwell and fled to Virginia as above mentioned. (Paxton, 7 et seq.) Senator Humphrey Marshall rejected this story as "a myth supported by vanity." (Ib.) Colonel Cary declares that "there is no evidence whatever in support of it." (Cary Papers, MSS.) Other painstaking genealogists have reached the same conclusion. ”
