Some of these are straight translations of the county's own name. Some are a war, a treaty or a grudge. And a few of the best known cannot be explained at all, which is said here rather than papered over.
A warning about the lists you will find elsewhere: they disagree with each other, and several of them give Tyrone the Oak Leaf County, which belongs to Derry. Tyrone is the Red Hand. Everything below is taken from one source for all thirty-two so the set is at least consistent with itself.
5 of the 32 have no settled origin, and they are marked. Tipperary is the surprise there: the Premier County is one of the best-known nicknames in the country and nobody can show where it came from.
For the nine glens that cut down to the sea along the north-east coast. It is one of the few nicknames that is simply a description of the ground.
For its apple orchards, which are old: Armagh has grown apples on a scale no other Irish county matches, and the Bramley is the crop it is known for.
For Bréifne, the kingdom that covered Cavan and Leitrim under the O'Rourkes and O'Reillys. The county is younger than the kingdom it is named for.
A modern nickname and a complaint: Donegal is the county most often left off the map, cut off from the rest of the Republic by the border and a long way from anyone making decisions.
For the Mourne Mountains in the south of the county, where Slieve Donard carries the highest known passage tomb in Britain or Ireland on its summit.
For Lough Erne, upper and lower, which take up so much of the county that Fermanagh is often said to be half water. Devenish Island and its round tower sit in the middle of it.
Straight from the name: Doire is an oak grove, and the city is Doire Cholm Cille, Colmcille's oak wood. The oak leaf is on the county crest.
For the drumlins, the low egg-shaped hills left by the ice that make the whole of south Ulster hard to cross and easy to hide in.
For the Red Hand of Ulster, the emblem of the O'Neills, whose seat at Dungannon was the capital of Gaelic Ulster until the Flight of the Earls in 1607. Popular lists often give Tyrone the Oak Leaf instead, which belongs to Derry.
For Browneshill dolmen outside Carlow town, whose capstone weighs something like 100 tonnes and is believed to be the heaviest in Europe. How Neolithic farmers raised it is still an open question.
Dublin has no single settled nickname the way the others do, and none appears in the standard reference. The Dubs is what people say, and the Pale is what the county was for four centuries.
For the Curragh and the horse country around it: the racecourse, the studs, and the flat limestone grassland that feeds them.
For Kilkenny marble, a black carboniferous limestone that polishes like marble without being any. It is in the kerbstones, the shopfronts and the cathedral.
For the O'Mores, lords of Laois, who fought the first plantation in Ireland for decades after their lands were confiscated in 1548 and the Fort of Leix was built where Portlaoise stands now.
No nickname appears in the standard reference. The Slashers is what is used, after Myles 'the Slasher' O'Reilly, who was killed at the bridge of Finnea in 1644.
Because it is the smallest of the thirty-two, at 826 square kilometres. Carlow is next and is seventy square kilometres bigger.
For Tara, where the high kings were inaugurated, and because Meath was once a province in its own right: the fifth fifth, in the middle, with the seat of the kingship inside it.
From the county motto, Esto Fidelis, be faithful. Which is a neat answer to a county that spent three centuries called King's County after an English king.
For Lough Ree, Ennell, Owel and Derravaragh, the last of which is where the Children of Lir were said to have spent the first three hundred years of their nine hundred as swans.
For its farming, which was held up in the 19th century as the model the rest of the country should copy. The Yellowbellies is the older and more argued-over name.
For the gardens and the glens: Powerscourt, Mount Usher, and the wooded valleys running down from the mountains within an hour of Dublin.
Nobody has settled it. One account has a banner captured from the enemy at Ramillies in 1706 by the Clare Dragoons of the Irish Brigade; another has the banners carried for Daniel O'Connell when he won the Clare election of 1828 and forced Catholic Emancipation. Both are good stories and neither is proven.
Cork backed Perkin Warbeck, the pretender to the English throne, in 1491, and the name stuck. It was taken up again, and meant differently, during the War of Independence.
The county's Irish name is Ciarraí, the people of Ciar, and Ciar was a son of Fergus mac Róich and Medb of Connacht. His kingdom is the kingdom in the nickname. It has since been claimed by the footballers.
For the Treaty of Limerick, signed in 1691 to end the Williamite war, and broken so quickly that Limerick has been called the city of the violated treaty ever since. The stone it was supposedly signed on still stands by the river.
The origin is not documented, which is unusual for a nickname this well known. It is variously put down to the richness of the Golden Vale, or to the Butlers, Earls of Ormond, whose seat was in the county. Neither can be shown.
For the Déisi, the people who held this country long before the county existed. Declan was their bishop, and brought Christianity to them before Patrick's mission was finished.
For the fourteen merchant families who ran the city for centuries: Blake, Joyce, Lynch, Bodkin and the rest. The name was originally an insult from Cromwellian forces, and the families took it up as a badge.
For the dog roses in the hedges, in the county with the smallest population and the least worked land in Ireland.
The name says it. Maigh Eo is the plain of the yew trees, and the nickname is a translation of the county's own name rather than anything added to it. The Maritime County is also used, for the Atlantic coast.
No nickname appears in the standard reference. The Rossies is what people say, and the Sheep Stealers is what their neighbours say.
For W. B. Yeats, who spent his childhood summers here and put the county into the poems: Innisfree on Lough Gill, the faeries at Glencar, and Ben Bulben, under which he asked to be buried and is.
The nicknames here are taken from one source for all thirty-two, the infobox of each county's Wikipedia article, because the popular lists disagree with each other and get things wrong. Where a nickname's origin is genuinely unknown, and a few of the best-known ones are, this says so rather than choosing the nicest story.
Each county's own page has the rest of it: who held the land in every age, the surnames that belong there, its towns and its castles. All thirty-two →