Seleucid power had begun to weaken after the defeat of Antiochus the Great at the hands of the Romans at the Battle of Magnesia in 190 BCE effectively broke Seleucid power and in particular the Seleucid army.

The Arsacids had taken power in Parthia and declared their full independence from the Seleucid Empire.

The Parthian king Mithridates I of Parthia invades Media, which is already in revolt against the Seleucid empire, in 148 BCE.

After winning a decisive battle at the Battle of Ecbatana, Mithridates is able to annex Media from the Seleucid Empire.

Andriscus’ conquest of Thessaly and alliance with Carthage makes the Macedonian situation dangerous.

A second Roman army under the praetor Quintus Caecilius Metellus in 148 defeats the pretender in the Second Battle of Pydna with relative ease and crushes the rebellion.

Andriscus, his brief reign marked by cruelty and extortion, flees to Thrace, whose prince gives him up to Rome.

The consul Spurius Postumius Albinus in 148 BCE constructs the Via Postumia, which runs from the coast at Genua (Genoa) …

…through the mountains to Dertona, …

…Placentia (the termination of the Via Aemilia Lepidi) and …

…Bedriacum, where it forks, …

…one branch running to the left to Verona and thence to the Brenner, …

…the other to the right to Mantua, …

…Altinum, and …

…Aquileia.

The military occupation of Liguria depends upon this road, and several of the more important towns owe their origin largely to it.