Siege of Pelium

Date	December, 335 BC
Location	Pelion (Chaonia) in modern-day Albania
Result	Macedonian victory.

Belligerents

Macedon,
Greek allies

Illyria

Commanders and leaders

Alexander the Great
Hephaestion

Cleitus the Dardanian
King Glaukias

Strength

15,000

Unspecified

The Siege of Pelium was undertaken by Alexander the Great against the Illyrian tribes of what is modern-day Albania. It was critical for Alexander to take this pass as it provided easy access to Illyria and Macedonia, which was urgently needed in order to quell the unrest in Greece at this time in Athens and Thebes. This was an important point of demarcation in Alexander's early reign, as it established him among the Danubian tribes to the north as a serious monarch to be reckoned with, just as he would later establish this precedent for the Greek city states under his hegemony. Taking this place allowed Alexander to march his army to southern Greece quickly, which would eventually result in the total destruction of Thebes.

News of the Illyrian revolt under Cleitus the Dardanian, and King Glaukias of the Taulanti first reached the ears of Alexander while he was campaigning on the Danube against some of the northern tribes that his father, Philip II of Macedon had previously reduced to a satisfactory level of subjection, although not outright submission. As this area had been far from the Greek theatre of operations, Phillip had been satisfied with the level of subjection he had reduced them to.

Alexander was immediately concerned about the news of this revolt, as the settlement of Pelium itself occupied one of the most important passes between Illyria and Macedonia. As a result of this, Alexander would have to make a long march around a mountain range to the south, and then into Illyria. In addition to this, without access to this crucial pass, Alexander could be cut off from Greece, which had freshly revolted, and would eventually do so again, with aid of the Great King. The loss of this pass, and the resultant long march would give the Greek city states to the south ample time to prepare for Alexander's arrival while he was reducing the Illyrians.

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Wikipedia