This is a complex question to answer.
In short, no the dative is not used, except by some speakers in Munsters. However in many dialects the historical dative form is actually used as the nominative form.
The Caighdeán however gives about 7-10 words (don't remember exactly how many) that one must use the dative with.
Complicating things even further however, native speakers don't really say Éire, but Éirinn.
"In Éirinn" is also used as an intensifier:
Ritheas chomh tapaidh in Éirinn agus ab fhéidir liom = I ran as fast as I could.
Ritheas = Rith mé