List of multinational festivals and holidays in December

Buddhism

• Bodhi Day: 8 December – Day of Enlightenment, celebrating the day that the historical Buddha (Shakyamuni or Siddhartha Gautama) experienced enlightenment (also known as Bodhi).

Christianity

• Advent: four Sundays preceding Christmas Day
• Krampusnacht: 5 December – The Feast of St. Nicholas is celebrated in parts of Europe on 6 December. In Alpine countries, Saint Nicholas has a devilish companion named Krampus who punishes the bad children the night before.
• Saint Nicholas' Day: 6 December
• Feast of the Immaculate Conception Day: 8 December – The day of Virgin Mary's Immaculate Conception is celebrated as a public holiday in many Catholic countries.
• Saint Lucia's Day: 13 December – Church Feast Day. Saint Lucia comes as a young woman with lights and sweets.
• Las Posadas: 16–24 December – procession to various family lodgings for celebration & prayer and to re-enact Mary & Joseph's journey to Bethlehem
• Longest Night: A modern Christian service to help those coping with loss, usually held on the eve of theWinter solstice. 
• Christmas Eve: 24 December – In many countries e.g. the German speaking countries, but also in Poland, Hungary and the Nordic countries, gift giving is on 24 December.
• Christmas Day: 25 December and 7 January – celebrated by Christians and non-Christians alike.
• Anastasia of Sirmium feast day: 25 December
• Twelve Days of Christmas: 25 December–6 January
• Saint Stephen's Day: 26 December – In Germany, Poland and the Czech Republic a holiday celebrated as Second Day of Christmas.
• Saint John the Evangelist's Day: 27 December
• Holy Innocents' Day: 28 December
• Saint Sylvester's Day: 31 December

Hinduism

• Pancha Ganapati: a modern five-day Hindu festival celebrated from December 21 through 25 in honor of Ganesha.

Historical

• Malkh: 25 December
• Modraniht: or Mothers' Night, the Saxon winter solstice festival.
• Saturnalia: 17–23 December – An ancient Roman winter solstice festival in honor of the deity Saturn, held on the 17 December of the Julian calendar and expanded with festivities through to 23 December. Celebrated with sacrifice, a public banquet, followed by private gift-giving, continual partying, and a carnival.
• Dies Natalis Solis Invicti (Day of the birth of the Unconquered Sun): 25 December – late Roman Empire

Humanism

• HumanLight: 23 December – Humanist holiday originated by the New Jersey Humanist Network in celebration of "a Humanist's vision of a good future."

Judaism

• Hanukkah: usually falls anywhere between late November and early January.

Paganism

• Pagan winter festival that was celebrated by the historical Germanic people from late December to early January.
• Yalda: 21 December – The turning point, Winter Solstice. As the longest night of the year and the beginning of the lengthening of days, Shabe Yaldā or Shabe Chelle is an Iranian festival celebrating the victory of light and goodness over darkness and evil. Shabe yalda means 'birthday eve.' According to Persian mythology, Mithra was born at dawn on 22 December to a virgin mother. He symbolizes light, truth, goodness, strength, and friendship. Herodotus reports that this was the most important holiday of the year for contemporary Persians. In modern times Persians celebrate Yalda by staying up late or all night, a practice known as Shab Chera meaning 'night gazing'. Fruits and nuts are eaten, especially pomegranates and watermelons, whose red color invokes the crimson hues of dawn and symbolize Mithra.
• Koliada: Slavic winter festival celebrated on late December with parades and singers who visit houses and receive gifts.

Secular

• Boxing Day: 26 December.
• Human Rights Day: 10 December
• Dongzhi Festival – a celebration of Winter
• Hogmanay: night of 31 December–before dawn of 1 January – Scottish New Year's Eve celebration
• Newtonmas: 25 December – As an alternative to celebrating the religious holiday Christmas, some atheists and skeptics have chosen to celebrate December 25 as Newtonmas, due to it being Isaac Newton's birthday on the old style date.
• Kwanzaa: 26 December–1 January – Pan-African festival celebrated in the US
• New Year's Eve: 31 December – last day of the Gregorian year 
• Soyal: 21 December – Zuni and Hopi
• Solstice: On or about 21 December.
• Zamenhof Day: 15 December – Birthday of Ludwig Zamenhof, inventor of Esperanto; holiday reunion for Esperantists
• Watch Night: 31 December

Unitarian Universalism

• Chalica: first week of December – A holiday created in 2005, celebrated by some Unitarian Universalists. 

Fictional or parody

• Erastide: In David Eddings' Belgariad and Malloreon series, Erastide is a celebration of the day on which the Seven Gods created the world. Greetings ("Joyous Erastide") and gifts are exchanged, and feasts are held.
• Feast of Winter Veil: 15 December–2 January – A holiday in World of Warcraft. This holiday is based on Christmas. Cities are decorated with lights and a tree with presents. Special quests, items and snowballs are available to players during this time. The character of "Greatfather Winter", who is modeled after Santa Claus, appears. Festival of the Winter Veil was and still is a legitimate holiday of European religions like Wicca. The Germanic tribes used to celebrate the Winter Solstice as a time to be thankful for the blessings given to them to survive harsh winters. The term "Weil", incorrectly translated to "veil", means abundance in German.
• Feast of Alvis: in the TV series Sealab 2021. "Believer, you have forgotten the true meaning of Alvis Day. Neither is it ham, nor pomp. Nay, the true meaning of Alvis day is drinking. Drinking and revenge."–Alvis
• Hogswatch: a holiday celebrated on the fictional world of Discworld. It is very similar to the Christian celebration of Christmas.
• Festivus: 23 December – a parody holiday created by Daniel O'Keefe and made popular by Seinfield as an alternative to Christmas.
• Frostvale: the winter holidays in the Artix Entertainment universe
• Decemberween: 25 December – a parody of Christmas that features gift-giving, carol-singing and decorated trees. The fact that it takes place on December 25, the same day as Christmas, has been presented as just a coincidence, and it has been stated that Decemberween traditionally takes place "55 days after Halloween". The holiday has been featured in the Homestar Runner series.
• Wintersday, the end-of-the-year celebration in the fictional universe of the Guild Wars franchise, starts every year mid December and ends the next year on early January.
• IES Competition Time, Don's Event questions on the number of trips he took all over the world and in return offering prizes for the person who can guess closest. Follows this up with everyone's favourite Andrew Award presentation.
• Winter's Crest, the winter celebration held on the continent of Tal'Dorei in the world of Exandria, as featured in the RPG show Critical Role. 

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Resources: www.gone-ta-pott.com / wikipedia.org / freedictionary.com / ChaseCalendar

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