Pleurias was an Illyrian king of the Autariatae

Autariatae

The Autariatae or Autariates were an ancient people that eventually became the most powerful Illyrian tribe. Their territory was called...

 State. In 337 BC

337 BC

Year 337 BC was a year of the pre-Julian Roman calendar. At the time it was known as the Year of the Consulship of Longus and Paetus...

 Pleurias almost succeeded in killing Philip when he was on his Balkan campaigns. Pleurias took on a minor role in the Illlyrian Revolt of 335 BC in blockading Alexander the Great advances southwards.

In 337 BC, Philip II

Philip II of Macedon

Philip II of Macedon "friend" + ἵππος "horse" — transliterated ; 382 – 336 BC), was a king of Macedon from 359 BC until his assassination in 336 BC. He was the father of Alexander the Great and Philip III.-Biography:...

's aim was to subdue the Autariatae State under Pleurias, during his Balkan campaigns. While Pleurias was engaged in a battle with Philip, he almost succeeded in in killing Philip if not for a bodyguard receiving Pleurias' sword. After ecieving on his body all the blows directed at Philip, the bodyguard died.

In 335 BC

335 BC

Year 335 BC was a year of the pre-Julian Roman calendar. At the time, it was known as the Year of the Consulship of Calenus and Corvus...

, Pleurias entered into an alliance with Gluacias of the Taulantii State and Cleitus

Cleitus the Illyrian

Cleitus was an Illyrian king of the Dardanian State attested in 335 BC. Cleitus was the son of Bardyllis and the father of Bardyllis II.....

 of the Dardanian State for the Illyrian Revolt. Cleitus had persuaded Pleurias to attack Alexander on his march south to meet him. On the meanwhile, Glaucias and Cleitus would join forces and meet Alexander at the city of Pelion

Pelion

Pelion or Pelium is a mountain at the southeastern part of Thessaly in central Greece, forming a hook-like peninsula between the Pagasetic Gulf and the Aegean Sea...

 in the south. Langarus

Langarus

Langarus , king of the Agrianians, was a contemporary of Alexander the Great , with whom he ingratiated himself even before the death of Philip II, previous king of Macedon. He rendered Alexander important services shortly after his accession, in his expedition against the Illyrians and...

, an ally of Alexander promised him that he would deal with the Autariatae State while Alexander would advance towards Cleitus. Langarus invaded their territory and defeated Pleurias, and thus brought a set back to Illyrian Revolt from the start.

In the 5th century BC the Autariate State reached it's peak of political and economic development. At the time of Pleurias' rule, the Autariatae State was in a decline due to the Celtic migrations. Pleurias's successors were followed by great hardship and by the gradual decline of the Autariatae State which eded in 310 BC

310 BC

Year 310 BC was a year of the pre-Julian Roman calendar. At the time, it was known as the Year of the Consulship of Rullianus and Censorinus...

with their sudden disappearance.