Saint Patrick's Saltire or Saint Patrick's Cross is a red saltire (X-shaped cross) on a white field. In heraldic language, it may be blazoned argent, a saltire gules. Saint Patrick's Flag (Irish: Bratach Naomh Pádraig) is a flag composed of Saint Patrick's Saltire. The origin of the saltire is disputed. Its association with Saint Patrick dates from the 1780s, when the Anglo-Irish Order of Saint Patrick adopted it as an emblem. This was a British chivalric order established in 1783 by George III. It has been suggested that it derives from the arms of the powerful Geraldine or FitzGerald dynasty. Some Irish nationalists opposed the usage of the flag to represent Ireland, as they considered it to be a British invention.
After its adoption by the Order of Saint Patrick, it began to be used by other institutions. When the Acts of Union 1800 joined the Kingdom of Ireland with the Kingdom of Great Britain, the saltire was added to the British flag to form the Union Flag still used by the United Kingdom. The saltire has occasionally served unofficially to represent Northern Ireland and also appears in some royal events.
