Religion in the Republic of Ireland
The predominant religion in the Republic of Ireland is Christianity, with the largest church being the Roman Catholic Church. The Irish constitution says that the state may not endorse any particular religion and guarantees freedom of religion.
Culture of Ireland
The national holiday in the Republic of Ireland is Saint Patrick's Day, that falls on the date 17 March and is marked by parades and festivals in cities and towns across the island of Ireland, and by the Irish diaspora around the world. The festival is in remembrance to Saint Patrick, the patron saint of Ireland. Pious legend credits Patrick with the banishing of the snakes from the island, and the legend also credits Patrick with teaching the Irish about the concept of the Trinity by showing people the shamrock, a 3-leaved clover, using it to highlight the Christian belief of 'three divine persons in the one God'.