Home Rule is what Scotland has. The 19th-century plan for Home Rule for Ireland was exactly what Scotland has now - a devolved parliament, but rule from Westminster.
The plan for this was given an amendment by a little-known MP called, I think, Agar-Roberts, which provided that four of the Ulster counties - Derry, Armagh, Down and Antrim - be temporarily held out from this.
But Home Rule was shelved during World War I, while 60,000 Irishmen, including half of Redmond's Irish Volunteers, went to fight in the English armies against Germany.
Then the Rising happened in 1916; and when the Volunteers came home from the war in 1918 many brought their service rifles with them and joined in the War of Independence, which included not only the usual warlike things - killing people, bombing out premises, etc - but also making the country ungovernable: the population largely ignored the Westminster government, Sinn Fein collected county council rates, county councils refused to give up their books to the British authorities for inspection.
In the elections nationalist MPs swept in - but formed their own national parliament and refused to sit in the British parliament. Thousands were jailed, and were again elected from jail.
A truce was declared in 1921 and the treaty signed with Britain established the Irish Free State in 1922; the bulk of the fighters held out from this and there was a terrible civil war, which ended with many of the republicans leaving Ireland for America.
The Republic of Ireland was declared in 1949. This republic includes the 26 counties; Derry, Antrim, Down and Armagh, Fermanagh and Tyrone - six of the nine Ulster counties - remain outside the Republic. So Ireland doesn't now have Home Rule; Ireland is a sovereign republic.
But getting back to the Scots national anthem - if not (and why not?) The Flower of Scotland, what about Caledonia? Though it's a bit syrupy.