Brian Friel's play "Making History" was first published in 1989. This version used English and Gaelic spellings, depending on the character. Hugh O'Neill is one character using the English spelling. Wikipedia suggests there is a version where all the names use Gaelic spellings. It doesn't cite which printing this is. While I don't think this printing exists, it doesn't hurt to check.
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To be clear, the Wikipedia page states that Hugh O'Neill and Hugh O'Donnell are alternately spelt "Aodh Mór Ó Néill" and "Aodh Rua Ó Domhnaill" in versions of the play, with the other characters apparently having the same spellings between versions, even though everyone in the play has multiple spellings that they have used. This info was added in November 2015 by Chrisdoyleorwell. It was unsourced. It remains unsourced.
Figuring out what version (if any) this is should not be too difficult, as Friel provides a character list in the first page. If we find that page, we can confirm the spelling for a printing.
Weird things about this:
O'Donnell is always referred to as Hugh O'Donnell, not Red Hugh O'Donnell, which was another valid name
The Baganal sisters would also have Gaelic spellings for their names
The 1989 printing has the standard names, which are the names most modern historians use
I'll see if I can find more info about Chrisdoyleorwell.
"Weekend? It's Monday already."
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