The national flag is a tricolour of green, white and orange. The tricolour is rectangular in shape, the width being twice the depth. The three colours are of equal size, vertically disposed, and the green is displayed next to the staff. The flag was first introduced by Thomas Francis Meagher during the revolutionary year of 1848 as an emblem of the Young Ireland movement, and it was often seen displayed at meetings alongside the French tricolour.
The green represents the older Gaelic and Anglo-Norman element in the population, while the orange represents the Protestant planter stock, supporters of William of Orange. The meaning of the white was well expressed by Meagher when he introduced the flag. "The white in the centre", he said, "signifies a lasting truce between the ‘Orange’ and the ‘Green’ and I trust that beneath its folds the hands of the Irish Protestant and the Irish Catholic may be clasped in heroic brotherhood."
It was not until the Rising of 1916, when it was raised above the General Post Office in Dublin, that the tricolour came to be regarded as the national flag. It rapidly gained precedence over any flag which had existed before, and its use as a national flag is enshrined in the Constitution.