Kwanzaa is fairly new; Christmas and Hanukkah have been around for ages. All three are in December, different views on a spiritual belief and three different ways to bond with the family.
Christmas has its beginning with the birth of Jesus Christ, as recorded in the Bible. After Emporer Constantine pronounced Christianity as the official religion of Rome, the faith began. These Christians embraced local winter-solstice rituals and changed them to reflect their faith in Christ. These Christians used such Solstice-ritual elements as trees, holly leaves, and Yule logs to celebrate the birth of God's hope to a world in darkness.
Hanukkah is a secondary Jewish holiday, less important than Passover and Yom Kippur. But because it falls in with the weeks before Christmas, it made its name of a secondary Christmas in many 20th-century in Jewish households.
As Leah Akins writes, Hanukkah origins date back to about 167 B.C. A Jewish army, led by Judah the Maccabee, recaptured Jerusalem from the Greeks (who had conquered the city during the reign of Alexander the Great, some three centuries before). Judah's men tried to re-consecrate the Jewish temple by lighting its menorah (a sacramental lamp). But, as the legend tells it, there was only enough of the special ritual oil to keep the menorah lit for one day. Interestingly enough, when they lit the lamp, it stayed lit for eight days--long enough for the Jews to make more oil. Over the years, the miracle of the oil became the central focus of Hanukkah celebrations. Families lit one candle on each of nine consecutive nights, remembering a different aspect of the holiday and of Jewish tradition.
Kwanzaa (means "first fruits" in Swahili) was originated by Dr. Maulana Ron Karenga in 1966. a holiday specifically for African-Americans. a celebration that would not replace any religious practices, but would rather focus on the heritage culture, and strengths of African-American families--"to reinforce the bonds between parents and children, and to teach parents and children new views and values that will aid them in self-consciousness and providing support and defense for our people." Each night during the week between Christmas and New Year's, families light candles on in-home shrines (decorated, according to Roz Fruchtman, in the colors of "black for the people, red for their struggle, and green for the future").
Resource
http://www.everythingchristmas.com/story/ckh.html