Many things, but most significantly, the famine.
Ireland's civil war happened between June 1922 and May 1923. It was fought between those who supported the treaty that gave independence to most of Ireland and those who did not support it.
Fourteenth Amendment of the Constitution of Ireland happened in 1992.
Third Amendment of the Constitution of Ireland happened in 1972.
St. Patrick came to Ireland.
Spanish Armada in Ireland happened in 1588.
Bruce campaign in Ireland happened in 1316.
Decimiaisation of currency happened in Ireland on the 15th of February, 1971.
It is not like that in Dublin and it never was like that. A common misconception is that there are problems all over Ireland between Catholics and Protestants. It is only in Northern Ireland that this happened, and although there are still some problems there, it is perfectly safe to even go there. So you need have no worries about coming to Dublin in terms of problems between Catholic and Protestants.It is not like that in Dublin and it never was like that. A common misconception is that there are problems all over Ireland between Catholics and Protestants. It is only in Northern Ireland that this happened, and although there are still some problems there, it is perfectly safe to even go there. So you need have no worries about coming to Dublin in terms of problems between Catholic and Protestants.It is not like that in Dublin and it never was like that. A common misconception is that there are problems all over Ireland between Catholics and Protestants. It is only in Northern Ireland that this happened, and although there are still some problems there, it is perfectly safe to even go there. So you need have no worries about coming to Dublin in terms of problems between Catholic and Protestants.It is not like that in Dublin and it never was like that. A common misconception is that there are problems all over Ireland between Catholics and Protestants. It is only in Northern Ireland that this happened, and although there are still some problems there, it is perfectly safe to even go there. So you need have no worries about coming to Dublin in terms of problems between Catholic and Protestants.It is not like that in Dublin and it never was like that. A common misconception is that there are problems all over Ireland between Catholics and Protestants. It is only in Northern Ireland that this happened, and although there are still some problems there, it is perfectly safe to even go there. So you need have no worries about coming to Dublin in terms of problems between Catholic and Protestants.It is not like that in Dublin and it never was like that. A common misconception is that there are problems all over Ireland between Catholics and Protestants. It is only in Northern Ireland that this happened, and although there are still some problems there, it is perfectly safe to even go there. So you need have no worries about coming to Dublin in terms of problems between Catholic and Protestants.It is not like that in Dublin and it never was like that. A common misconception is that there are problems all over Ireland between Catholics and Protestants. It is only in Northern Ireland that this happened, and although there are still some problems there, it is perfectly safe to even go there. So you need have no worries about coming to Dublin in terms of problems between Catholic and Protestants.It is not like that in Dublin and it never was like that. A common misconception is that there are problems all over Ireland between Catholics and Protestants. It is only in Northern Ireland that this happened, and although there are still some problems there, it is perfectly safe to even go there. So you need have no worries about coming to Dublin in terms of problems between Catholic and Protestants.It is not like that in Dublin and it never was like that. A common misconception is that there are problems all over Ireland between Catholics and Protestants. It is only in Northern Ireland that this happened, and although there are still some problems there, it is perfectly safe to even go there. So you need have no worries about coming to Dublin in terms of problems between Catholic and Protestants.It is not like that in Dublin and it never was like that. A common misconception is that there are problems all over Ireland between Catholics and Protestants. It is only in Northern Ireland that this happened, and although there are still some problems there, it is perfectly safe to even go there. So you need have no worries about coming to Dublin in terms of problems between Catholic and Protestants.It is not like that in Dublin and it never was like that. A common misconception is that there are problems all over Ireland between Catholics and Protestants. It is only in Northern Ireland that this happened, and although there are still some problems there, it is perfectly safe to even go there. So you need have no worries about coming to Dublin in terms of problems between Catholic and Protestants.
Ireland has over 8000 years human occupation, so there is a lot of history there. Much happened before that, so a huge amount of things have happened in Ireland. Therefore your question is impossible to answer in detail.
There are 32 counties in Ireland, 6 of which are in the North (Northern Ireland) Does this help? Slan go foil
First Amendment of the Constitution of Ireland happened in 1939.
Eleventh Amendment of the Constitution of Ireland happened in 1992.