It could be said that all Gaels were/are Irish or Scottish but not all Irish or Scottish were/are Gaels. This must have been so for many centuries or why such place names as Dún na nGall'(Donegal) and a plethora of villages and townlands called 'Baile na nGall' (Ballinagaul, Ballynagoul, etc) around the country? The names mean 'Fort of the Foreigners' and 'Settlement of the Foreigners'. However, the Gael seemed to be adept at absorbing the foreigners over time, whether Picts or Norsemen or Saxons, as these places are often in the Gaeltacht districts of today.

Of course its also possible that sometimes the original 'foreigners' that caused the place-name might merely have been interlopers from another part of Gaeldom, speaking a variant dialect of Gaelic.

But what if the Picts were the earlier inhabitants of Ireland as well as Scotland and that Pictish was a language akin to Gaelic. Then those particular place-names could refer to the Gaelic interlopers. It would also explain why Pictish is such a mystery language and why the Picts were so apparently readily absorbed into the new Scottish kingdom, adopting Gaelic and generally leaving so little trace of their separate existance. Scottish Gaelic might even be the result of the new combination,