Kerry is bounded by the Atlantic Ocean on the west and the River Shannon on the north, with County Limerick to the east and County Cork to the south and east. With 4,807 square kilometres and 156,458 people as of 2022, it is the fifth largest of Ireland's thirty-two counties by area and the fifteenth by population. The coastline is cut by three great peninsulas - Dingle, Iveragh, and Beara - each fingering westward into the Atlantic. The MacGillycuddy's Reeks on Iveragh rise to over 1,000 metres. Carrauntoohil, the highest mountain in Ireland at 1,039 metres, sits at the heart of this range. The Blasket Islands and the Skelligs lie offshore. Skellig Michael, with its medieval monastery clinging to cliff terraces, is a World Heritage Site. The county's interior is mostly flat, interspersed with the Stacks and the Mullaghareirks - low ranges that look modest only by comparison with Carrauntoohil.

Kerry has two official Gaeltacht regions: Gaeltacht Uibh Rathaigh on the Iveragh Peninsula and Gaeltacht Corca Dhuibhne on the Dingle Peninsula. Corca Dhuibhne is the only Gaeltacht in the entire province of Munster where Irish is the daily spoken language of the majority of the population. The dialect is Munster Irish, exemplified in the influential books that came out of the Blasket Islands in the early twentieth century - works by Peig Sayers, Muiris O Suilleabhain, and Tomas O Criomhthain. The Blaskets were evacuated in 1953, when the weather and isolation made continued habitation impossible. Their books outlived them. In 2011, 6,083 Irish-speakers lived in the county, 4,978 of them native speakers within the Kerry Gaeltacht. Outside the Gaeltacht, another 1,105 children attended Irish-language schools - Gaelscoils and Gaelcholaiste - bringing the language back into a wider Kerry that English had nearly replaced.

Kerry was hammered by the Great Famine of 1845-49. Its population dropped 19 percent between the censuses of 1841 and 1851, and emigration continued until the 1980s. The Kerryonians, an early Irish criminal gang in nineteenth-century New York, took their name from this county. Kerry was also one of the counties most affected by the Irish War of Independence and the bitter civil war that followed. In November 1920, the Black and Tans burned homes and shot civilians in Tralee in retaliation for the IRA killing of five local policemen. Five months later, the Headford Junction ambush near Killarney killed about ten British soldiers, three civilians, and two IRA men. After the Anglo-Irish Treaty of 1921, most Kerry IRA units opposed the settlement. The county became, perhaps, the worst-affected area of the civil war. In March 1923, in reprisal for an ambush, National Army soldiers tied republican prisoners to mines and detonated them. The most notorious of these atrocities was Ballyseedy, near Tralee, where eight men were killed. Two of them survived to tell what had happened. The internecine violence ended in May 1923. The bitterness it produced shaped Kerry politics for generations.

In 1580, during the Second Desmond Rebellion, one of the most infamous massacres of the sixteenth century took place at Dun an Oir near Smerwick on the Dingle Peninsula. A 600-strong Italian, Spanish, and Irish papal invasion force led by James Fitzmaurice FitzGerald was besieged by English forces and, after their surrender, massacred. The siege left a permanent scar on the western tip of Kerry - a name spoken with weight, even four and a half centuries later. The same county now produces Ireland's most successful Gaelic footballers. The Kerry senior team has won the Sam Maguire cup thirty-nine times. Hurling never quite took hold here at the same level - only one All-Ireland Senior Hurling title, in 1891 - but football is the language of the place. John B. Keane, the Listowel playwright behind The Field, Sive, and Big Maggie, is considered one of Ireland's greatest. The annual Listowel Writers' Week celebrates Irish writing in a town that has been giving Ireland its writers for generations.

Kerry has an unusual density of archaeological sites - dating from the Mesolithic, the Neolithic, the Bronze Age, and the Iron Age. Atlantic rock art carvings, distinct from the megalithic art at Newgrange, cluster especially on the Iveragh and Dingle peninsulas. Bronze Age standing stones, wedge tombs, boulder burials, and stone circles dot the landscape. Iron Age forts hold high ground. Early Christian ring forts, churches, cross-inscribed stones, holy wells, and ogham stones survive across the county. Each layer reflects centuries of habitation in a place that, because of its position at the western edge of Europe, has tended to preserve what other places erase. The subtropical plants that grow at this latitude - the strawberry tree, tree ferns - thrive because of the North Atlantic Current. The same warm current carried the survivors of the famine to the New World, and brought their descendants back as tourists a century later, looking for the names their families had left behind.