Census of Population in Ireland
Censuses of population have been conducted in Ireland since 1841. Beginning in 1951, these censuses have been undertaken at 5 yearly intervals with the exceptions of 1976 and 2001.
Census data is a rich source of information about the population of Ireland, immigration, into Ireland and emigration from Ireland. The published reports provide detailed information on the diversity of newcomers to Ireland, their living arrangements, educational attainments, occupations etc.
The most recent Census took place on the 10th of April 2011. The 2011 form contained two additional sections relating to languages spoken in the home and the level of proficiency in spoken English of those who spoke languages other than English or Irish at home, as well as a question on perception of health. General information about the Census was available in 21 languages. A copy of the Census was also available in 21 languages for information purposes.
You can see below some analysis taken from the first definitive results from the 2011 Census in the publication "This is Ireland - Highlights from Census 2011 Part 1". A later report "Profile 6: Migration and Diversity" provides the detailed comprehensive analysis of the figures for non-Irish nationals living in Ireland, including information about foreign languages spoken and ability to speak English. Further Census 2011 reports were made available throughout 2012 and you can find links to them in this table.
"This is Ireland" in a preliminary analysis showed the following: -
Ireland's population is 4,588,252 which is an increase of 348,404 (i.e. up 8.2% since the 2006 Census).
The number of Irish residents who were born outside Ireland continues to increase and was 766,770 in 2011 (i.e. 17% of the population). This is an increase of 25% on the 2006 Census figure. This figure of 766,770 includes 241,985 Irish nationals born abroad, of whom 178,945 were born in the UK, 16,703 in US, 3,220 in Australia, 2,524 in Canada and 2,440 in South Africa.
There were 544,357 (which is 12% of the population) non-Irish nationals from 199 different nations usually resident and present in Ireland at the time of Census 2011. This is an increase of 29.7% since 2006. The increase is 143% between 2002 and 2011.
Polish nationals were the largest non-Irish nationality grouping - they showed a 93.7% increase from 63,276 persons in 2006 to 122,585 in 2011.
UK nationals (formerly the largest non-Irish national group) are now the second largest group with 112,259 living in Ireland in 2011.
The breakdown by nationality of the 544,357 non-Irish nationals who were usually resident and present in the State at the time of the Census shows that the vast majority came from within the EU, i.e. 386,764 or 71% as illustrated by the charts below. The largest groups of Third Country Nationals (non-EU 27 nationals) come from Asia (65,579) followed by Africa (41,642).
Of the 386,764 non-Irish nationals with EU nationality, the highest group were from Poland (122,5850, followed by the UK (112,259).
The chart below shows the breakdown of of non-Irish nationals from the EU 27 (excluding Ireland).