Wikipedia
Celtic
* Samhain: November 1 - first day of winter in the Celtic calendar (and Celtic New Year's Day)
* Winter Solstice: December 21~December 22 - midwinter
* Imbolc: February 1 - first day of spring in the Celtic calendar
Chinese
* Dong zhi: Winter solstice
* Signature of the Constitution of the Republic of China (Taiwan) : December 25 - a secular national holiday, which due to its date is celebrated in some respects like Christmas
* Chinese New Year (late January - early February) - considered the end of winter in the traditional Chinese calendar
Christian
* Advent: four weeks prior to Christmas - preparing for the birth of Christ.
* Saint Nicholas' Day: December 6
* Christmas Eve: December 24
* Christmas: December 25 - the birth of Christ.
* 12 Days of Christmas: December 25 through January 6
* Saint Stephen's Day: December 26
* Saint John the Evangelist's Day: December 27
* Holy Innocents' Day: December 28
* Saint Sylvester's Day: December 31
* Watch Night: December 31
* Feast of the Circumcision: January 1
* Feast of Fools: January 1
* Twelfth Night: Epiphany Eve January 5
* Epiphany - January 6: the arrival of the Three Magi.
* Eastern Orthodox Christmas according to the Julian Calendar: January 7
* Candlemas: February 2
* St. Valentine's Day: February 14
Germanic
* Modranect: or Mothers' Night, the Saxon winter solstice festival.
* Yule: the Germanic winter solstice festival
Jewish
* Hanukkah: Starting on 25 Kislev (Hebrew) or various dates in December (Gregorian) - eight day festival commemorating the miracle of the oil after the desecration of the Temple by Antiochus IV Epiphanes and his defeat in 165 BCE.
Pagan and Neopagan
* Yule: (Winter Solstice) - Germanic Pagan festival of the rebirth of the Sun
* Imbolc : (February 1 or 2) - festival of candles
* Winter Solstice: (December 21) - New Age festival
Persian
* Yalda: (Winter Solstice) - Birth of Sun God Mehr
* Sadeh: waiting for arriving of the summer from 50 days before in the winter.
Polynesian
* Matariki: (Maori New Year, usually early June) - Rising of the Pleiades star cluster before dawn.
Roman
* Saturnalia: the Roman winter soltice festival
* Festival of the birth of the Unconquered Sun: late Roman Empire - December 25
* Hedgehog Day, the archaic European version of Groundhog Day, dating back to Roman times - February 2
* Lupercalia, the Roman end-of-winter festival - February 15
Secular
* Quebec City Winter Carnival - February - Annual celebration of winter.
* Yulefest - June - Australian "Christmas in Winter"
* Winterval - secular name for winter festivities coined by Birmingham City Council to encompass all holidays being recognized from October to January
* Agnostica - Celebrating the birth of quantum physics.
* Zamenhof Day - December 15 - Birthday of Ludwig Zamenhof, inventor of Esperanto; holiday reunion for Esperantists
* HumanLight - December 23 - recently invented Secular Humanist midwinter holiday originated by the New Jersey Humanist Network
* Chrismukkah - slang term for the amalgam of Christmas and Hanukkah celebrated by religiously mixed families and couples
* Yuletide - December 25 - classic and modern, respectively, terms for the social and federal December 25th holiday
* Boxing Day - December 26 - gift-giving day after Christmas.
* Kwanzaa
* Hogmanay - December 31 - Scottish New Years Eve
* New Years Eve - last day of the Gregorian year
* New Year's Day - January 1 - first day of the Gregorian year
* Burns Night - January 25 - birthday of Robert Burns
* Groundhog Day - February 2
Slavic
* Karachun - the pagan winter solstice festival
Zen Buddhist
* Rohatsu
* Samhain: November 1 - first day of winter in the Celtic calendar (and Celtic New Year's Day)
* Winter Solstice: December 21~December 22 - midwinter
* Imbolc: February 1 - first day of spring in the Celtic calendar
Chinese
* Dong zhi: Winter solstice
* Signature of the Constitution of the Republic of China (Taiwan) : December 25 - a secular national holiday, which due to its date is celebrated in some respects like Christmas
* Chinese New Year (late January - early February) - considered the end of winter in the traditional Chinese calendar
Christian
* Advent: four weeks prior to Christmas - preparing for the birth of Christ.
* Saint Nicholas' Day: December 6
* Christmas Eve: December 24
* Christmas: December 25 - the birth of Christ.
* 12 Days of Christmas: December 25 through January 6
* Saint Stephen's Day: December 26
* Saint John the Evangelist's Day: December 27
* Holy Innocents' Day: December 28
* Saint Sylvester's Day: December 31
* Watch Night: December 31
* Feast of the Circumcision: January 1
* Feast of Fools: January 1
* Twelfth Night: Epiphany Eve January 5
* Epiphany - January 6: the arrival of the Three Magi.
* Eastern Orthodox Christmas according to the Julian Calendar: January 7
* Candlemas: February 2
* St. Valentine's Day: February 14
Germanic
* Modranect: or Mothers' Night, the Saxon winter solstice festival.
* Yule: the Germanic winter solstice festival
Jewish
* Hanukkah: Starting on 25 Kislev (Hebrew) or various dates in December (Gregorian) - eight day festival commemorating the miracle of the oil after the desecration of the Temple by Antiochus IV Epiphanes and his defeat in 165 BCE.
Pagan and Neopagan
* Yule: (Winter Solstice) - Germanic Pagan festival of the rebirth of the Sun
* Imbolc : (February 1 or 2) - festival of candles
* Winter Solstice: (December 21) - New Age festival
Persian
* Yalda: (Winter Solstice) - Birth of Sun God Mehr
* Sadeh: waiting for arriving of the summer from 50 days before in the winter.
Polynesian
* Matariki: (Maori New Year, usually early June) - Rising of the Pleiades star cluster before dawn.
Roman
* Saturnalia: the Roman winter soltice festival
* Festival of the birth of the Unconquered Sun: late Roman Empire - December 25
* Hedgehog Day, the archaic European version of Groundhog Day, dating back to Roman times - February 2
* Lupercalia, the Roman end-of-winter festival - February 15
Secular
* Quebec City Winter Carnival - February - Annual celebration of winter.
* Yulefest - June - Australian "Christmas in Winter"
* Winterval - secular name for winter festivities coined by Birmingham City Council to encompass all holidays being recognized from October to January
* Agnostica - Celebrating the birth of quantum physics.
* Zamenhof Day - December 15 - Birthday of Ludwig Zamenhof, inventor of Esperanto; holiday reunion for Esperantists
* HumanLight - December 23 - recently invented Secular Humanist midwinter holiday originated by the New Jersey Humanist Network
* Chrismukkah - slang term for the amalgam of Christmas and Hanukkah celebrated by religiously mixed families and couples
* Yuletide - December 25 - classic and modern, respectively, terms for the social and federal December 25th holiday
* Boxing Day - December 26 - gift-giving day after Christmas.
* Kwanzaa
* Hogmanay - December 31 - Scottish New Years Eve
* New Years Eve - last day of the Gregorian year
* New Year's Day - January 1 - first day of the Gregorian year
* Burns Night - January 25 - birthday of Robert Burns
* Groundhog Day - February 2
Slavic
* Karachun - the pagan winter solstice festival
Zen Buddhist
* Rohatsu
This is just meant to be a nice, somewhat accurate, list of all the holidays people celebrate around this time of year.
