Ireland 1926 census by county — population, Irish speakers, and change to 2022

The 1926 census was the first conducted by the Irish Free State — a nation two years past civil war, five years past independence, with 2.97 million people across 26 counties. By 2022 that figure was 5.15 million. But the growth was not evenly distributed. Kildare's population grew by 327%. Leitrim's fell by 37%. This is where that century of change happened — county by county.

Ireland 1926 census — key figures

Population by county — 1926 vs 2022, ranked by change

All 26 counties ranked by population change from 1926 to 2022 (CSO Census). Irish speakers % from the 1926 census (habitual speakers — the strict Gaeltacht definition, not comparable to modern census methodology).

Sources: CSO Census 1926 (TNLIA01, TNLIA02, HCA34) · CSO Census 2022. Irish speaker figure = habitual/native speakers as recorded in 1926 — methodology differs from 2022 census.

The counties that grew — where Ireland concentrated

Five counties more than doubled their 1926 populations. All of them orbit Dublin or sit along the east coast.

• Kildare (+327%): smallest county population in 1926 among the midlands. By 2022 it held 247,774 people — driven by Dublin commuters along the M7, rail links to Heuston, and large-scale housing development in Naas, Newbridge, Maynooth, and Celbridge. Kildare was 27% agricultural in 1926; manufacturing and services now dominate.
• Meath (+250.7%): 62,969 people in 1926, 220,826 in 2022. Navan, Ashbourne, Ratoath, and Dunboyne absorbed successive waves of Dublin overspill along the M1, M2, and M3. Census 2022 recorded the fastest population growth of any county in the 2016–2022 period — Meath is still absorbing Dublin.
• Dublin (+188.4%): already the largest county in 1926 at 505,654. By 2022 it held 1,458,154 — almost one in three Irish people. The increase of 952,500 people is larger than the entire 1926 population of the next three counties combined.
• Wicklow (+170.6%): DART access from Bray and Greystones transformed the north of the county from a farming and mining area into a Dublin dormitory. South Wicklow retained more rural character — the north drove almost all the growth.
• Louth (+122.7%): smallest county geographically. Drogheda became a major growth centre on the Dublin–Belfast corridor; Dundalk developed significant manufacturing and cross-border retail. Louth's population more than doubled despite losing some agricultural base in the midlands portion.

The counties that lost population — rural Ireland's long decline

Six counties recorded lower populations in 2022 than in 1926. Five are in the west and northwest.

• Leitrim (−37%): 55,907 people in 1926. 35,199 in 2022 — a loss of 20,708 people over a century despite a small mid-century recovery. Leitrim was 47% agricultural in 1926, the highest agricultural dependency in the state. As tillage and livestock farming became mechanised, the labour was no longer required. Young people emigrated; the county never replaced them. Census 2022 records a median age of 44 in Leitrim — among the highest nationally — and an owner-occupancy rate of 82%, reflecting a county where property is accessible precisely because demand is low.
• Mayo (−20.1%): 172,690 in 1926 — the fifth largest county. 137,970 in 2022. Mayo had one of the highest agricultural dependency rates (46%) and one of the highest Irish speaker rates (36.8%). The combination of subsistence farming and geographic isolation made it one of the primary counties of the post-independence emigration wave. Unlike the Celtic Tiger recovery which concentrated growth near Dublin, Mayo saw limited employment growth. Westport and Castlebar grew; rural Mayo continued to hollow.
• Roscommon (−15.9%): landlocked, predominantly agricultural (46% in 1926), no major urban centre. Roscommon town and Boyle saw modest growth; rural townlands continued to depopulate. Census 2022 records 70,259 people — fewer than in 1926.
• Sligo (−1.7%): nearly flat over the century — but masks significant internal redistribution. Sligo town grew substantially; rural Sligo declined sharply. The net figure conceals a dramatic shift from dispersed rural settlement to urban concentration.
• Cavan (−0.9%): essentially unchanged in population over 96 years. Cavan's 1926 Protestant population (10,102 — 12.3% of county) was notably higher than most southern counties, reflecting the Ulster border county composition.

The Gaeltacht in 1926 — where Irish was still a living language

The 1926 census recorded Irish speaker rates under the strict definition of habitual or native speakers — the living Gaeltacht communities of the new state. These are not comparable to the 2022 census figures, which use a different methodology. They represent the actual geographic distribution of the language in 1926.

• Galway (47.4%): highest rate of any county. Connemara and South Galway contained the most extensive Gaeltacht communities in Ireland. Galway city itself had a more mixed profile — the county average reflects the strength of Irish in the rural west.
• Mayo (36.8%): Erris, Achill Island, and the Tourmakeady area were strong Gaeltacht communities. The combination of Irish speaking and high agricultural dependency would characterise the counties most affected by twentieth-century emigration.
• Donegal (34.4%): the Donegal Gaeltacht — the Rosses, Gweedore, and the Fanad Peninsula — was geographically isolated from the rest of Ireland by the border. Donegal's 1926 Protestant population (nearly 19% — among the highest in the Free State) reflects its Ulster border character.
• Kerry (33.0%): the Dingle Peninsula and Iveragh Gaeltacht. Kerry's overall population change was almost flat (+4.9%) over the century — the county neither grew significantly nor declined, retaining a demographic character more similar to 1926 than most counties.
• Clare (30.3%): the Aran Islands (administered under Clare at the time) and coastal West Clare had significant Irish-speaking communities. Clare sits on the edge of the traditional Connacht Gaeltacht zone.
• Waterford (22.8%): the Ring/An Rinn Gaeltacht on the Waterford coast is one of the smallest but most geographically distinct — an Irish-speaking enclave in an otherwise English-speaking county. The 1926 figure reflects the concentration of speakers in that coastal area.

1926 census overview →  ·  How Ireland changed →  ·  Irish language 1926 →

Population growth 2016–2022 →  ·  Rural Ireland today →