The population of Co Kildare has grown massively over the past century, with the 1926 Census showing an increase of 327% in the county, while Co Leitrim, Co Mayo and Co Roscommon saw decreases in their population sizes.
The National Archives have released the 1926 Census of Population records, which show that Ireland's population was 2.97 million that year.
The Central Statistics Office (CSO) has compared the first census conducted by the Irish Free State in 1926 to the most recent census in 2022 looking at population, employment, occupation and religion.
The population had grown to 5.15 million in 2022, an increase of 73% since 1926.
The largest population growth by far was in Kildare where the population increased by 327% from just over 58,000 in 1926 to almost 248,000 in 2022.
It was followed by Meath, which saw its population grow by 251% and Dublin by 188%.
The data shows that life expectancy has since risen by more than 20 years for both males and females who were now expected to live to their early 80s.
Life expectancy at birth was 57 years for males and 58 years for females in 1926 but by 2022 life expectancy at birth was 81 years for males and 84 years for females.
In 1926, Roman Catholics made up 93% of the population, while by 2022 this had fallen to 69% with Monaghan recorded as having the lowest proportion in the state with 79%, compared to the national average of 93%.
Wicklow had the highest Church of Ireland population at 15%, significantly above the national average of 6%.
Dublin was the most religiously diverse county, with the largest Jewish population and the highest Methodist share, alongside a lower Catholic proportion (86%) than most counties.
The data found that in 1926, 97% of people living in Ireland were Irish born and less than 1% were born outside Ireland, Northern Ireland, and Great Britain.
By 2022, the Irish born share was 80% and 14% of residents were born outside Ireland, Northern Ireland, and Great Britain.
There was a much larger and more diversified workforce in 2022 than existed a century earlier with around one million more people working compared to 1926.
Over the past century employment has moved from being dominated by agriculture and manual labour to managerial, professional and non-manual roles in 2022.
Agriculture dominated the labour market in 1926 making up 51% of the entire workforce but by 2022, this had fallen to almost 4%.
The gender profile of the workforce changed substantially, in 1926 74% were men and 26% were women, while in 2022 the workforce was spread more evenly with 53% men and 47% women.
Maria Yasin, Statistician in the Census Division of the CSO, said: "Some notable jobs in 1926 included 10,852 horse vehicle drivers, 1,441 saddlers, 1,012 coopers (cask and barrel makers) and 211 chimney sweepers, of which one was female."
She said the health service in 1926 was far smaller with 2,051 medical doctors, 491 midwives, 5,341 sick nurses, and 536 dentists recorded.
"By 2022, we can also see a substantial shift to specialised roles, particularly in the areas of IT and finance," she added.
