Watched Days

On 15 October 1582, ten days that never happened had just been skipped. In the countries that switched calendars, the day before was 4 October: 5 through 14 October 1582 do not exist. No births, no records, nothing to watch.

Italy, Spain, Portugal, France and the Catholic Low Countries moved that month. Britain waited until 1752, by which time the drift had grown to eleven days: Wednesday 2 September was followed by Thursday 14 September. The Act shifted rents, salaries and market days with it so nobody lost a fortnight. It is why the UK tax year still ends on 5 April, eleven days on from Lady Day.

Letters from the crossing years carried two dates, Old Style and New Style, because one morning had two names depending on whose post it arrived in.

Source: Wikipedia, Gregorian calendar and Calendar (New Style) Act 1750, checked 15 October 2026.