Cross-border flag for Ireland

There is no cross-border flag universally accepted as representing both jurisdictions in Ireland. This can be a problem in contexts where a body organised on an all-island basis needs to be represented by a flag in an international context. The island is politically divided into the Republic of Ireland (a sovereign state comprising 26 of Ireland's 32 counties) and Northern Ireland (comprising the remaining 6 counties in the north-east of Ireland and a part of the United Kingdom), but all-island organisations are common. Examples include the Roman Catholic Church in Ireland, the Presbyterian Church in Ireland and the Church of Ireland, the Gaelic Athletic Association, and the Irish Rugby Football Union.

The Saint Patrick's Saltire was incorporated into the Union Flag in 1801 by way of the Act of Union 1800 to represent Ireland within the new United Kingdom of Great Britain and Ireland. Today, those who regard the tricolour as specific to the Republic of Ireland, or excluding unionists, may advocate it as a neutral symbol of the whole island.

The Church of Ireland orders that, apart from the flag of the Anglican Communion, only this saltire may be flown on its church grounds—as opposed to the tricolour, the Union Flag or the former flag of Northern Ireland. This follows the practice of other Anglican churches in England, Scotland, and Wales, which fly the flags of their respective patron saints instead of the Union Flag.

The saltire is also flown by St. Patrick's College, Maynooth, on graduation days, and so it can be argued that St. Patrick's Saltire is used by the main Protestant church on the island and the Roman Catholic Church.

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Wikipedia