Hanukkah is a Jewish holiday that celebrates the liberation of Jerusalem from the occupation of Antiochus IV, king of the Seleucid Empire in 165 BCE . There are many traditions surrounding the holiday, including gift giving, eating fried foods, listening to music and playing with dreidels. These traditions are part of why the holiday has grown in prominence and popularity. Read on to find out more about the mystery and history of Hanukkah.
The death of Alexander the Great in 323 BCE (Before Common Era) left a tremendous power vacuum in the lands which had composed his enormous empire. Alexander's remaining generals took control of the regions, and eventually four main generals controlled a majority of the territories. Ptolemy reigned over Egypt, Seleucus reigned over Babylon, Cassender Macedonia, and Lysimachus reigned over Thrace.1 Seleucus had the most power, and shortly after the division of lands defeated Lysimachus in battle, absorbing those lands as well. His kingdom stretched from Turkey and Syria to India, and this eventually became known as the Seleucid Empire. His only real threat after the conquest of Lysimachus was Ptolemy, who controlled Palestine and Egypt 1.
Around 222 BCE, Antiochus III became the 6th king of the Seleucid Empire. 3 In 198 BCE, Antiochus attacked the Ptolemies in the Battle of Panium, and won. It was during this battle that Antiochus and the Seleucid Empire took effective control of Jerusalem.3 As an effect of these conflicts, there grew two separate groups of Jewish people in Jerusalem, those that remained loyal to the Ptolemaic Empire of Egypt, and those that were loyal to the Seleucid Empire, also known as Hellenistic Jews.
10 years after Antiochus' victory against the Ptolemies, he died. His son Selecus IV initially took the throne, but was assassinated shortly thereafter 1. Another ruler, Antiochus IV, replaced him.
From Machabees 1 "
 And there came out of them a wicked root, Antiochus the Illustrious, the son of king Antiochus, who had been a hostage at Rome: and he reigned in the hundred and thirty-seventh year of the kingdom of the Greeks."5
When Antiochus III had originally conquered Jerusalem, he allowed the Jews to retain their religious practices. However, when Antiochus IV gained control, he gave special favor to the Hellenistic Jews. According to several sources, the Tobiad family, a family of Hellenistic Jews, convinced Antiochus IV to make many changes in Jerusalem. They began implementing Greek culture into Jewish culture, including a construction of a gymnasium, and many Jews ceased practicing Jewish customs.
From Machabees 1 "
 And the word seemed good in their eyes.
 And some of the people determined to do this, and went to the king: and he gave them license to do after the ordinances of the heathens.
 And they made themselves prepuces, and departed from the holy covenant, and joined themselves to the heathens, and were sold to do evil."5
Between 175 BCE and 168 BCE, there was a power struggle between the conservative Jews and the Hellenistic Jews to gain control of Jerusalem.
Around 168 or 167 BCE, Antiochus IV returned to Jerusalem from Egypt, and ordered his troops to desecrate and loot the Second Temple in Jerusalem. In addition, he ordered them to build a statue of Zeus there, and ordered the troops to murder many Jewish people.
From Machabees 1 "
 And he went up to Jerusalem with a great multitude.
 And he proudly entered into the sanctuary, and took away the golden altar, and the candlestick of light, and all the vessels thereof, and the table of proposition, and the pouring vessels, and the vials, and the little mortars of gold, and the veil, and the crowns, and the golden ornament that was before the temple: and he broke them all into pieces.
 And he took the silver and the gold, and the precious vessels: and he took the hidden treasures which he found: and when he had taken all away he departed into his own country.
 And he made a great slaughter of men, and spoke very proudly."5
While many Jewish people had converted to the Greek religion, many also did not, and refused to convert as Antiochus had ordered them to do. Eventually, those who refused to convert as Antiochus had commanded gathered together under Judas, son of Mathathias, and formed an army 10,000 strong. Lysias, who had been appointed as viceroy by Antioch, also formed a large army in order to capture the dissenters.
From Machabees 4 "
 So the year following Lysias gathered together threescore thousand chosen men, and five thousand horsemen, that he might subdue them.
 And they came into Judea, and pitched their tents in Bethoron, and Judas met them with ten thousand men."
The two armies clashed, and 5,000 of Lysias' troops were slain. When Lysias saw that the Jews were destroying his army and were prepared to die for their cause, he retreated and went to the king to get more troops. As Lysias retreated, Judas announced to the Jews that they should go and clean all of the holy places that had been desecrated. When the Jews went to the temple, they cleaned and sanctified it. They then made a sacrifice on the new altar and a dedication using harps, lutes, cymbals and canticles. They decorated the temple with gold and other adornments. The dedication lasted eight days, and is now known as the celebration of Hanukkah.5
According to Wikipedia, the Book of Talmud states that the Jews used olive oil to light the menorah in the Temple. While there was only enough olive oil for the menorah to be lit for one day, the Talmud states that the menorah remained lit for the entire eight day dedication.4
5. The Holy Bible, Douay-Rheims Version.