Great Famine (Ireland)

30 March 1851: the count

The all-Ireland census was conducted on 30 March 1851, during the famine's late phase. It counted 6,552,385 people on the island, against 8,175,124 in 1841 — a recorded decline of 1,622,739, or 19.85 percent.

That number is not a death toll. Census totals measure net population change, so the gap combines mortality, emigration, births and possible enumeration error.

Leaving, at the peak

Transatlantic emigration reached its famine-era peak during 1851, when just under a quarter of a million people left Ireland.

Better harvests after 1849 had eased pressure across much of the island, but localized blight and famine conditions continued in southwestern districts through 1852. Poor Law unions went on supporting destitute people while the worst-hit western and southwestern districts stayed under strain.

The volumes, and the fire

The Ireland Census Office recorded the demographic consequences visible by 1851. The volumes examining famine disease and mortality were prepared in part by the physician and census commissioner William Wilde.

1851 was neither the beginning nor the worst year of the famine; the heaviest mortality came earlier, especially during Black '47. What the year supplies is the measurement rather than a new calamity.

Most individual returns from the census that measured the catastrophe were destroyed in the 1922 Public Record Office fire.