Battle of Elasa

The Battle of Elasa was fought between Jewish and Seleucid armies during the Maccabean Revolt against the Seleucid Empire.

Background
In 160 BC, the Seleucid King Demetrius, on campaign in the east, left his general Bacchides to govern the western portion of the empire. Bacchides led an army of 20,000 infantry and 2,000 cavalry into Judea intending to reconquer this now independent kingdom.

The Seleucid general Bacchides hastily marched through Judea after carrying out a massacre in the Galilee. He quickly made for Jerusalem, besieging the city and trapping Judas Maccabeus, the spiritual and military leader of Judea, inside.

1 Maccabees records that Judah's army consisting of 3,000 men were terrified of such a large force and two thirds of them deserted, leaving Judah with 800-1,000 soldiers (1 Maccabees, and Flavius Josephus respectively). Judah encouraged his remaining men and set out to meet the Seleucid army in the rough terrain surrounding Jerusalem.

The battle
Being heavily outnumbered, Judah ignored the Seleucid infantry which had deployed in the slow moving and inflexible phalanx formation, instead launching an all out attack on Bacchides himself, who was part of the Seleucid cavalry squadron on the right flank of the army. They succeeded in quickly routing Bacchides' cavalry, who fled into the steep hills that surround Jerusalem, with the Judeans in hot pursuit. Meanwhile, the left flank of Seleucid cavalry had been racing to meet up with the right flank, and in doing so surrounded and fought against the Judeans in the hills. The Seleucid infantry may or may not have caught up. If they did catch up, despite being unable to properly deploy in phalanx formation due to the terrain, and not being trained or equipped properly for individual hand to hand combat, they would still have managed to turn the battle easily with their sheer numbers. Judah was eventually killed and the remaining Judeans fled.

Betzalel Bar Kochva, an Israeli historian, believes that the Judeans would have had equal numbers to the Seleucids in this battle, that Bacchides' retreat was feigned in order to lure Judah into a vulnerable position, and that the Seleucid phalanx managed to best the Judean phalanx in a full-scale battle. It is noteworthy that he has no sources for this theory, but develops his surmise after establishing the likely organization of a Judean military.

Aftermath
The Seleucids had reasserted their authority temporarily in Jerusalem, but Judah's brother Jonathan and after him Simon, continued to fight, meeting Bacchides again in later battles. Eventually, after several additional years of war under the leadership of Judah's brothers and the defeat of Bacchides several times by both Jonathan and later Simon, Seleucid control of Judea was broken. The descendants of Simon established the Hasmonean dynasty which, due largely to internal strife, would last only around 100 years.