Barclays bank in Ireland?

they have barclays bank in northern ireland, im from england and moved to ireland in 2000 and i closed my barclays account to re-open a bank of ireland account in waterford, only to be told barclays and BOI link together so barclays could have taken care of this for me and just 're-located' my account into the bank of ireland network.

ive heard other irish banks do this.....ulster bank of course is tied to nat west and i think allied irish bank is tied to llyods but i might be wrong.