Barnaby Fitzpatrick, 2nd Baron Upper Ossory (c. 1535 – 11 September 1581), was educated at the court of Henry VIII of England with Edward, Prince of Wales.

On his departure on 9 December 1552, he was warmly commended for his conduct by Henry himself and the Constable Montmorency[6] During his residence in France, Edward VI continued to correspond regularly with him[b] On his return to England Fitzpatrick took an active part in the suppression of Wyatt's rebellion (1553).

In 1574 the Earl of Ormond made fresh allegations against Fitzpatrick's loyalty, and he was summoned to Dublin to answer before the council, where he successfully acquitted himself.

In 1576 he succeeded his father, who had long been impotent, as Baron Upper Ossory, and two years afterwards had the satisfaction of killing the great rebel Rory O'More.

[13] Owing to a series of charges preferred against him by Ormond, who declared that there was "not a naughtier or more dangerous man in Ireland than the baron of Upper Ossory",[14] Fitzpatrick and his wife were on 14 January 1581 committed to Dublin Castle.

Fitzpatrick seems to have been suddenly taken ill, and on 11 September 1581, he died in the house of William Kelly, surgeon, Dublin, at two o'clock in the afternoon.

[19] He was, said Sir Henry Sidney, "the most sufficient man in counsel and action for the war that ever I found of that country birth; great pity it was of his death".

[21][22] While the popular image of young Sir Barnaby as Edward VI's whipping boy persists on the basis of their great friendship, historian Leanda de Lisle has noted the lack of contemporary evidence for this scenario, suggesting it is a modern popular myth based on assumptions stemming from the later development of the Divine right of kings.