In 1752, the British Empire adopted the Gregorian calendar. In the British Empire that year, September 2 was immediately followed by September 14.
The Gregorian calendar is also known as the Western Calendar or the Christian Calendar. They don’t use it in Russia, for example, so what we call the October revolution actually happened in November, there. The Gregorian Calendar is based upon the Julian Calendar (which Julius Caesar invented), but it makes the year a fraction shorter (365.25 days — 365 days 6 hours — to 365.2425 days — 365 days 5 hours 49 minutes 12 seconds, a reduction of 10 minutes 48 seconds per year). This allowed Easter to align with the spring Equinox. Without that adjustment, Easter would drift further and further from the Equinox each year.
Because of the “errors” the old calendar had accumulated, in 1752 the calendar skipped two weeks to bring everything back into alignment.
Wouldn’t it have been hilarious if someone had stumbled to bed, very drunk, on September 2 and woke up to think they’d slept through two whole weeks? 🙂