In 1971.
February 1971
1845 to 1852.
Because the previous system was very complicated and computers and calculators would have had difficulty calculating in the old system which was superseded by decimalisation in 1971.
1801
During the period from 1845 to 1852, Ireland suffered a famine due to the potato crop getting potato blight which destroyed the crop.
Prior to decimalisation there were 240 pennies in 1 pound. This was stated as 240d = £1 One modern penny = 2.4 old pennies at the time of decimalisation in February 1971.
Four predecimal British Pennies convert to 1.666 New Pence at decimalisation.
They are not something that happen in Ireland.
1972
No
Spanish Armada in Ireland happened in 1588.
Bruce campaign in Ireland happened in 1316.
Prior to decimalisation, there were 240 Pennies in a British Pound. On decimalisation, there are 100 Pennies in a British Pound.
February 1971
1921
Ireland has many rivers and lakes and can get a high amount of rainfall. As a result flooding does often happen in parts of Ireland.
First Amendment of the Constitution of Ireland happened in 1939.