The first night of Hanukkah this year falls on December 24, or Christmas eve.
In the Jewish calendar, Hanukkah begins at sundown on the 25th of a month called Kislev, and it continues for eight days. The Jewish calendar is partly lunar and partly solar, whereas the Gregorian (Western secular) calendar is purely solar. The Jewish calendar and the Gregorian calendar do not overlap precisely, and that’s why Hanukkah keeps “moving around” the secular calendar, sometimes starting as early as the tail end of November and sometimes not starting until after Christmas Day.
Although Jews make up less than 2% of the U.S. population, in the last few decades Hanukkah has taken a prominent place in mainstream American culture. The increase over the last two generations in the number of interfaith families in America is one of the reasons for the “mainstreaming” of Hanukkah in American culture, as the percentage of Americans who have a relative who celebrates Hanukkah has grown steadily during this era. If you aren’t sure when Hanukkah falls in any given year, just look it up here.