this would have been more prevalent in the past when the Christian Brothers gaelicised every surname. I too have a "foreign" surname though my forbears have been in this country at least 300 years. Often the translation varied from one part of the country to another and even from one teacher to another. So I suppose William Shakespeare would have been forced to change his name to Liam O'Criothclaibh.or something like that.
"The rich always betray the poor"- Henry Joy McCracken
Are you sure there's no Irish version of your surname? After all, if it's been in Ireland since Elizabethan times there could very well be.
You could also have told the school in advance not to put an Irish version of your surname on any documents instead of flying off the handle at what seems like a fairly innocent practice with no ill intentions.
If it were me I don't think it would bother me, but then I'm aware that's just me. Since it does bother you then you are of course perfectly correct to let them know as much - and never mind such begrudgers as are sure to turn up here at some stage trying to out-Irish you.
I'm intrigued, though, by the notion brought up in the OP - are there daft buggers ofteachers out there trying to gaelicise Polish, Nigerian & other names without guidance or even permission? Perhaps even more intriguingly, is there perhaps a leaflet from the Dept of Ed or elsewhere that gives guidance on doing this?
If anyone tells E O'Cuív (talking about gaelicised names!) about this he's sure to put a raft of civil servants on the job!
Give these fellas a lash:
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I posted in the Education and Science Forum, I thought that was appropriate, and while my post is not not about politics in the party-political sense, it touches upon the intensely political (with a small p) subjects of Irish language policy and cultural sensitivity.
Or Fitzgerald (fils de Gerard) to Mac Gerailt. Or Costello (de Angulo) to Mac Coisdealbha.
Gaelicizing surnames is nothing new and is certainly not something to get upset about. Just have your child instruct the teacher that she'd prefer to use her 'original' surname.
Some original Irish names were also highly anglicized beyond any recognition in the past so although wrong she could have been acting in good faith.