After 1,000 years I feel it is a little early to make any decisions without more probing. Am sure there were more White Knights floating about as I found some that were connected with the Fitzgerald / McDonnell family in co. Ulster about the same time. Then there was the one in 1613 - Calendar of State Papers - Ireland. Index: Knight, the White, p.173 surity for Florence McCarthy, p.486 forfeited lands of.
no. 640. page 331.March 31st 1613. Philad. P., vol. 2, p. 126 - The King to Lord Chichester - By the attainder, in the reign of the late Queen, of John Fitzgerald, commonly called the White Knight, otherwise called John Oge FitzJohn, Knight Fitzgibbons, all his manors, castles, lands, etc. came to the Crown, and were afterwards granted by her late Majesty to Edmund Fitzgibbon, commonly called the White Knight, and the heirs male of his body, the reversion being in the Crown. And understanding that the said Edmund is now dead without issue male, he (the King) directs that all the lands which came to the Crown by the attainder of the said John Fitzgerald, which have not been granted heretofore to any other person, and are now in charge, together with the lands granted to the said Edmund Fitzgibbon in tail, be granted to his well-beloved servant Sir Patrick Murray, one of the gentlemen of his Privy Chamber, in consideration of his long and faithful service done to the King. - Last day of March, in the eleventh year of the reign.
Keep them coming Joe ! I love to be found wrong, that way in the end we may end up with something that is right.