Fun fact, the vast majority of Canadian population live more southern than anywhere in Ireland, James Bay (southernmost point of Hudson's Bay) shares roughly the same latitude with Co. Cork.
Is 'In the north of Canada' wrong, then?
Yes — see my reply to Dia_duit.
Is "Our friends are living in northern Canada" an acceptable translation?
No — thuaidh i gCeanada is in reference to the speaker, not in reference to Canada. “In northern Canada” would be i dtuaisceart Cheanada (literally “in (the) north of Canada”; this is an expression where English needs an article and Irish doesn’t).
Go raibh maith agat!
Why is "Our friends are living in the north in Canada" wrong?
Cén fath go bhfuill in the north of micheart