The Dictionary of Statistics by Michael G. Mulhall, London, George Routledge and Sons, 1892

I have been browsing through the above book and found many interesting population, emigration and property statistics relating to Ireland in the 19^th century. These statistics reveal the impact the artificial famine of the 1840s had upon the population of Ireland which had already been reduced to destitution and serfdom by centuries of British misrule. (The illustration "The Irish remedy -- emigration to America," seen here, is by Staniland, Charles Joseph, 1838-1916 from Wallach Division Picture Collection, New York Public Library.

Population of Ireland at various dates (estimated and by census calculation)

1066 = 1,000,000
1381 = 1,100,000
1528 = 770,000
1672 = 1,320,000
1712 = 2,099,000
1754 = 3,200,000
1780 = 4,200,000
1801 = 5,216,000
1811 = 5,957,000
1821 = 6,802,000
1831 = 7,768,000
1841 = 8,197,000
1851 = 6,574,000
1861 = 5,799,000
1871 = 5,412,000
1881 = 5,160,000
1889 = 4,716,000

In 1841 there were 256 inhabitants per square mile
In 1889 there were 150 inhabitants per square mile

Continuing emigration, combined with a fall in marriages and births, would see the Irish population decline throughout the late 1800s and well into the 20^th Century.
In 1870 there were 150,000 births in Ireland, but by 1889 the total had fallen to 108,000
In 1870 there were 29,000 marriages, but by 1889 the total had fallen to 21,000

Famine

Cornelius Walford (Insurance Cyclopedia, London, 1878) mentions that since the 11^th Century there had been 34 famines in Ireland

The famine of 1741, “The Year of Slaughter”, killed 250,000-400,000
“An Gorta Mór”, the Great Hunger of 1846-47 killed 1,009,000

Deaths from hunger and destitution in 1879:
Ireland 37.6 per 1,000 deaths
England 0.6 (London 1.2)
France 0.3

Emigration from Ireland:

1815-34 = 420,000
1835-50 = 1,409,000
1851-60 = 1,231,000
1861-70 = 867,000
1871-80 = 542,000
1881-88 = 677,000

Total for 74 years = 5,081,000 Irish emigrants
Compared with 845,000 Scottish and 3,935,000 English (English & Welsh)

Not included in the above total are the Irish emigrants who settled in Britain. The 1841 Census shows that on the eve of An Gorta Mór there were already 419,256 Irish living in Britain. The 1851 Census reveals that the number of Irish in Britain had risen to 727,326, an increase of 308,070, and by the time of the 1861 Census the total had increased to 805,717.

Destination of Irish emigrants:

United States = 4,074,000
Canada = 480,000
Australia = 440,000
Cape &c = 87,000
Total = 5,081,000

Remittances by Irish settlers in USA to friends at home, from 1851 to 1887 amounted to £32,200,000 equivalent to £5,293,680,000 (£1 in 1890 is equivalent to £164.40 today)

The 1880 US census showed that there were:

1,855,000 Irish
1,967,000 Germans
917,000 British
376,000 Scandinavians
107,000 French
44,000 Italians

In 1884 there were 22,000 Irish living in the province of Buenos Ayres, owning 4,900 square miles of land, and 9,200,000 sheep!

Land

Even by the late 1870s most of Ireland was still owned by a relatively small number of landlords, many of whom were absentee landlords living outside Ireland but stripping the country of its wealth and resources.

In 1878 the Local Government Board reported that 32,610 people owned estates of more than one acre, totalling 20,150,000 acres. 18,100 people had estates from 1 to 100 acres, totalling 474,000 acres but a mere 14,510 people had estates from 100 to over 500 acres, totalling 19,676,000 acres.

A report from 1880 stated that 1,623 people, owning 4,514,000 acres were absentee landlords, and another 4,465 people, owning 4,362,000 acres were not living on their estates but were residents in Dublin.

In 1841 there had been 691,000 tenant farmers, but by 1851 the total had fallen to 570,000 tenants.

Houses:

In 1887 the rental value of house property in Ireland was £3,500,000 with a total value of £63,000,000
The rental value of house property in Scotland, was £12,600,000 with a total value of £228,000,000, some 3.6 times greater than that of Ireland, even though Scotland’s population was smaller (1889 = Ireland 4,716,000, Scotland 4,077,000).

The number of ‘houses’ in Ireland in 1841 was 1,328,000 with 6.2 people per house on average
In 1851 there were 1,046,000 with 6.3 people per house
In 1871 there were 962,000 with 5.6 per pouse
In 1881 there were 914,000 with 5.7 per house

In 1841, of the 1,328,000 houses, 491,000 were of one room (most of these would have been the simple, mud, stone, and thatch peasants’ hovels that can still be seen lying in ruins in the west of Ireland)
In 1871, 156,000 were of one room, a reduction of 335,000 houses (a consequence of ‘famine’ deaths, forced eviction and emigration).