Act 24 of George II rectified an anomaly between the English and most continental European calendars by removing from history the days of 3rd-13th September 1752 and thereafter starting each year on January 1st rather than March 25th.
The Roman calendar had used January 1st as the first day of the year from 153 BCE onwards, but most medieval Christian calendars used March 25th, the Feast of the Annunciation. The Anglo-Saxons celebrated New Year on December 25th, and William the Conqueror decreed January 1st should be New Year's Day, but pressure from the Catholic Church later brought England into line with continental religious practice …
Clark, Robert. "Calendar Reform". The Literary Encyclopedia. First published 01 May 2004; last revised 25 September 2008.
[http://www.litencyc.com/php/stopics.php?rec=true&UID=141, accessed 28 March 2017.]