Three out of four people living in Wales at the time of the 2001 Census were born in Wales (75 per cent). A further 20 per cent were born in England, 2 per cent were born in other UK countries or Ireland, and 3 per cent were born in countries outside the UK.

The proportion of people resident in Wales who were born in Wales has declined over the post-war period. At the time of the 1951 Census, 83 per cent of people living in Wales were born there. This fell to 77 per cent in 1991 and 75 per cent in 2001.

By contrast, the proportion of English-born people living in Wales increased during this period. Whereas in 1951 fewer than one in seven people living in Wales were born in England, by 2001 this had grown to more than one in five.

The proportion of people who were born in Wales differs markedly across Unitary Authority areas, with the highest proportions found in South Wales. In both Blaenau Gwent and Merthyr Tydfil 92 per cent of residents were born in Wales, followed by Caerphilly, Rhonda Cynon Taff (90 per cent each) and Neath Port Talbot (89 per cent).

The northern border authority of Flintshire had the lowest proportion of residents born in Wales, only 51 per cent. Conwy and Powys had the next lowest proportions, 54 and 56 per cent respectively.

Across Wales the youngest residents are those most likely to be born in the country, as would be expected. Among children aged under 16 years, 87 per cent were born in Wales. In half of the 22 Unitary Authority areas, nine out of ten children were born in Wales, although in Powys and Flintshire it was only six out of ten.

The proportion of people living in Wales who were born in Wales tends to decline with age, from 87 per cent of those under 16, to 74 per cent of those aged 16 to 34, and to 71 per cent aged 35 to 64. However, among those aged 65 and over the proportion increased slightly to 72 per cent.

Across the country the picture was much more varied, in part reflecting local differences in people migrating to study, work, or retire. In the band of five south Wales authorities from Neath Port Talbot to Caerphilly the proportion of residents born in Wales was consistently high across all age groups (above 85 per cent) while in Flintshire it was consistently low (around 50 per cent).

In Cardiff the proportion of adults born in Wales increased with age, while in Conwy and Denbighshire the proportion declined sharply so that pensioners born in Wales were outnumbered by their English-born counterparts. In Conwy only one in three of those aged 75 and over was born in Wales.
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From being, at the beginning of the 19th century, a mere village in an agricultural district, the place grew rapidly in population owing to the abundance of its coal and iron ore, and the population of the whole parish (which was only 1486 in 1801) increased tenfold during the first half of the century.
Population only 1486 - just two hundred years ago!
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The population of Wales in the 2001 census was 2,903,085, which has risen to 2,958,876 according to 2005 estimates. This would make Wales the 132nd largest country by population if it were a sovereign state.
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