1582

The year 1582 marks the introduction of the Gregorian calendar, which replaced the Julian calendar to improve calendar accuracy. The Julian calendar had accumulated a drift of about 10 days over centuries, causing dates of important events to shift. To correct this, Pope Gregory XIII issued a reform: October 4, 1582, was followed directly by October 15, 1582, skipping 10 days. This adjustment realigned the calendar with the solar year, ensuring that seasonal dates, especially those related to the equinoxes and church holidays, remained consistent. The Gregorian calendar is used internationally today.