The <a href="https://en.wikipedia.org/wiki/Julian_calendar" id="mwIA" rel="mw:WikiLink" title="Julian calendar">Julian calendar</a> takes effect as the civil calendar of the Roman Empire, establishing January 1 as the new date of the new year.<sup about="#mwt23" class="mw-ref reference" data-mw='{"name":"ref","attrs":{},"body":{"id":"mw-reference-text-cite_note-2"}}' id="cite_ref-2" rel="dc:references" typeof="mw:Extension/ref"><a href="./January_1#cite_note-2" id="mwIQ" style="counter-reset: mw-Ref 2;"><span class="mw-reflink-text" id="mwIg">[2]</span></a></sup>
<span class="mw-reference-text reference-text" id="mw-reference-text-cite_note-2"><cite about="#mwt20" class="citation book cs1" id="mwDLU"><a class="external text" href="https://books.google.com/books?id=u-_gTMsfSgIC&amp;pg=PA103" id="mwDLY" rel="mw:ExtLink nofollow"><i id="mwDLc">Origines Kalendariae Italicae Nundinal Calendars of Ancient Italy, Nundinal of Calendar of Romulus, Calendar of Numa Pompilius, Calendar of the Decemvirs, Irregular Roman Calendar, and Julian Correctio Tables of the Roman Calendar, from V. C. 4 of Varro, B. C. 750, to V. C. 1108 A. D 355. 4 by Edward Greswell, B.D: Vol. 4</i></a>. University Press. 1854. p.<span id="mwDLg" typeof="mw:Entity"> </span>103.</cite><span about="#mwt20" class="Z3988" id="mwDLk" title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Origines+Kalendariae+Italicae+Nundinal+Calendars+of+Ancient+Italy%2C+Nundinal+of+Calendar+of+Romulus%2C+Calendar+of+Numa+Pompilius%2C+Calendar+of+the+Decemvirs%2C+Irregular+Roman+Calendar%2C+and+Julian+Correctio+Tables+of+the+Roman+Calendar%2C+from+V.+C.+4+of+Varro%2C+B.+C.+750%2C+to+V.+C.+1108+A.+D+355.+4+by+Edward+Greswell%2C+B.D%3A+Vol.+4&amp;rft.pages=103&amp;rft.pub=University+Press&amp;rft.date=1854&amp;rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3Du-_gTMsfSgIC%26pg%3DPA103&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AJanuary+1"></span></span>