The Gregorian calendar is the internationally accepted civil calendar, used in most of the world. It was introduced in 1582 by Pope Gregory XIII and is based on the solar year.
The Gregorian calendar replaced the Julian calendar to correct its drift against the solar year. It introduced the leap year rule and quickly became the global standard for civil use. Most international holidays, national observances, and public events follow this calendar.
The Gregorian calendar includes many holidays celebrated around the world, both religious and secular. While dates and traditions vary by culture, these are among the most widely observed:
- New Year’s Day – January 1
- Valentine’s Day – February 14
- International Women’s Day – March 8
- St. Patrick’s Day – March 17
- Good Friday – Date varies (March or April)
- Easter Sunday – Date varies (March or April)
- Earth Day – April 22
- Labor Day / International Workers’ Day – May 1
- Mother’s Day – Second Sunday in May (many countries)
- Father’s Day – Third Sunday in June (many countries)
- Independence Day (U.S.) – July 4
- Bastille Day (France) – July 14
- Halloween – October 31
- All Saints’ Day – November 1
- Remembrance Day / Veterans Day – November 11
- Thanksgiving (U.S.) – Fourth Thursday in November
- Christmas Day – December 25
- Boxing Day – December 26
- New Year’s Eve – December 31
The Gregorian calendar includes a leap year every four years, except for years divisible by 100 unless they are also divisible by 400. This system keeps the calendar aligned with Earth’s revolution around the Sun, maintaining long-term accuracy.
Many countries have unique holidays tied to their culture and history. For example, the United States celebrates Independence Day on July 4, France celebrates Bastille Day on July 14, and India observes Republic Day on January 26.
Major holidays include New Year’s Day, Easter, Christmas, and other national celebrations that vary by country.
It is used globally as the civil calendar and is the basis for most international date systems.
It was introduced in 1582 by Pope Gregory XIII, replacing the Julian calendar to better align with the solar year.