Hugh O'Donnell, 2nd Earl of Tyrconnell (October 1606 – August/September 1642) (originally known in Irish as Aodh mac Rudhraighe Ó Domhnaill), was titular King of Tír Conaill, and son of Rory O'Donnell, 1st Earl of Tyrconnell whose title was however attainted.
Aodh (Hugh), was three weeks shy of his first birthday he sailed from Lough Swilly during the Flight of the Earls, and was raised in Leuven. In time he joined the service of the King of Spain, and was killed in action when his ship engaged a French vessel in August or September 1642 and caught fire. He left no immediate heirs, although the Earldom, were it not attainted in 1614, would have passed by remainder to his uncle Cathbharr, whose line was extinct by then, and thence, to his 1st cousin Donal Oge O'Donnell, according to the terms of the letters patent.
Hugh O'Donnell in 1632
Knowing that up-time weapons and tactics would change the nature of warfare, Hugh O'Donnell went to Grantville to learn what he could about them.[n 1] While in Grantville, he acquired copies of infantry training manuals, and the design for a 5-barrel cap-and-ball pepperbox revolver that could be produced by gunsmiths in the Netherlands. After returning from Grantville, he began to introduce these innovations.
- This is referred to after the fact. While it is implied that this happened relatively close to the events of "Birds of a Feather", when he went and how long he stayed is not definitely stated. It is also not known if he went openly or incognito.