Adoption of Gregorian Calendar

The Gregorian calendar was adopted and the old Julian calendar abandoned by the ‘Calendar (New Style) Act 1750’ that received Royal Assent on 27 May 1751. It came into effect on 1 January 1752. The body of the Act included:

‘In and throughout all his Majesty’s dominions and countries in Europe, Asia, Africa, and America, belonging or subject to the crown of Great Britain, the said supputation, according to which the year of our Lord beginneth on the twenty-fifth day of March, shall not be made use of from and after the last day of December one thousand seven hundred and fifty-one; and that the first day of January next following the said last day of December shall be reckoned, taken, deemed, and accounted to be the first of the year of our Lord one thousand seven hundred and fifty-two ... .’

Ireland, as a separate kingdom and having its own parliament, passed almost identical legislation titled ‘Calendar (New Style) Act 1750’.

Dates before 1752 are often followed by (O.S.) to indicate that they are dates in the ‘Old Style’ or (N.S.) to indicate that they are dates in the ‘New Style’, the former being Julian and the latter Gregorian.