This is a festival which lasts eight days, commencing on 25 Kislev. It recalls the miracles and wonders that were wrought for our forefathers and marks the victory of the Hasmoneans over the Greeks, after which the Temple was purified and religious freedom was restored, followed by political freedom.
The main events associated with Hanukkah occurred between 165 and 163 BCE. Hanukkah is, therefore, one of the festivals that originated in the post-Biblical period. The historic events of the festival are described in the First Book of Maccabees, one of the books of the Apocrypha. It is not actually a festival in the full sense of the term and no restrictions apply to work or to any other activity during its eight days.
The First Book of Maccabees sets out the steps taken by the Hellenist Greek-Syrians to eliminate the Jewish religion, among them the profanation of the Temple in Jerusalem, as part of their plan for Hellenization of their whole kingdom.
The altar was desecrated when the Syrian ruler, Antiochus Epiphanes, commanded that it be used for offering sacrifices to pagan gods. After a three-year struggle, the Hasmoneans, under the leadership of Judah the Maccabee, conquered Jerusalem, destroyed the desecrated altar and built it anew. They also made new utensils for the Temple service, among them a menorah (candelabra), an incense altar, table and curtains.
According to Talmudic tradition, the eight days of Hannukah were determined in memory of the wonderful miracle that occurred at the rededication of the Temple. Not enough pure oil was found to light the Temple menorah, just one container which had been with the seal of the High Priest [and so was untouched and undefiled] but it had sufficient oil for only one day. A miracle happened and the oil in it lasted for eight days. “The following year these [days] were appointed a Festival with [the recital of] Hallel [literally: praise. The reference is to Psalms CXIII - CXVIII, which are recited on all Festivals] and thanksgiving.” (Talmud, Tractate Shabbat 21b).