Thanks for your question.
Potentially, I believe there is an arrangement where a person born in Northern Ireland can obtain an Irish passport. Whilst this applies to your grandmother a person can potentially claim Irish nationality through birth, marriage, naturalisation and decent. Your claim is through decent via you grandmother.
This is an Irish law question and the Irish Embassy can advise further.
1. Dear Lee, you have an entitlement to an Irish passport because you have a grandmother born on the island of Ireland. Go to www.inis.gov.ie the website of the Irish Immigration and Naturalisation Service where you can download the forms to fill in to apply for an Irish passport. Be aware that all persons with a grandparent born in Ireland can claim an Irish passport. This includes all person born in Northern Ireland because for Irish citizenship purposes, the jurisdiction of Ireland extends to the whole island of Ireland.
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