Cappadocia under Ariarathes IV had come into relations with Rome, first as a foe espousing the cause of Antiochus the Great, then as an ally against Perseus of Macedon.

The kings henceforward had throws in their lot with the Republic as against the Seleucids, to whom they had been from time to time tributary.

Ariarathes V marches with the Roman proconsul Publius Licinius Crassus Dives Mucianus against Aristonicus, a claimant to the throne of Pergamon, and their forces are annihilated in 130 BCE.

The imbroglio that follows his death will ultimately lead to interference by the rising power of Pontus and the intrigues and wars that end in the failure of the dynasty.

Antiochus, with Palestine secured, now devotes his attention to recovering the Seleucid domains in the east.

He assembles a powerful army, which once more includes men of Persis and Elymais.

The strength in numbers and the wealth of this army make an impression on contemporaries, who report that even the simple soldiers wear shoes cobbled with gold.

With enthusiastic support from the Hellenized cities, …

…Antiochus drives the Parthians from Mesopotamia and Babylonia and …

…invades Media, where, with the arrival of winter, he quarters his troops in several localities.

Parthian ruler Mithridates I had died in 138 BCE; his son and successor rules as Phraates II.

The Parthians, perhaps hopeful of stirring up civil war behind Antiochus, release his brother Demetrius, who has been their prisoner for a decade.

Roman consul Publius Licinius Crassus Dives Mucianus, who had become Pontifex Maximus in 132 BCE after the death of the exiled Pontifex Publius Cornelius Scipio Nasica Serapio, had in the following year been elected consul along with Lucius Valerius Flaccus, the flamen Martialis.

Mucianus, according to ancient historians, was a wealthy, cultivated man who spoke several varieties of Greek fluently.

He and his brother were supportive of political and economic reforms, and as such, staunch supporters of Tiberius Sempronius Gracchus (killed in 133 BCE), who was married to his wife's niece, another Claudia.

Crassus Mucianus later marries his younger daughter to Tiberius's younger brother Gaius.

Mucianus had forbidden his colleague to fight against Aristonicus and fined him for neglecting his sacred duties.

The people remitted the fine but wished Flaccus to submit to his religious superior.

Mucianus nevertheless has come east to fight Aristonicus; he is the first Pontifex Maximus to voluntarily leave Italy (whereas Scipio Nasica Serapio had been sent out of Italy by the Senate).

He meets with defeat in 130 and, while retreating, is overtaken by the enemy and stabbed to death; according to one source (Valerius Maximus), he deliberately refused to reveal his identity to avoid the humiliation of being captured alive.

Emperor Han Wudi’s reign sees great territorial expansion and a burst of economic and cultural activity.

His armies push north and west into central Asia, east to Korea, and south to the coast.

Commerce with the states of western Asia increases, silk becomes a major export, and inventors discover ways to make paper and porcelain.

Han historiographer Sima Qian writes Shiqi (Shih chi) ("The Records of the Historians"), which will serve as the prototype for the official histories of successive dynasties.

Han scholars direct their efforts to find or reconstruct the Zhou classics banned during the Qin dynasty.

Confucianism begins to replace Legalism as the Han dynasty’s orthodox philosophy.

The Seleucid–Parthian wars have brought about a lasting cultural exchange between East and West.

Greek ideas will be remembered in the East long after they have been forgotten about in the West, while Persian and Indian influences in sciences, literature and architecture will be introduced to western powers such as the Romans.

The westward expansion of Parthia during the war will eventually lead to clashes with the Roman Empire.

The Roman–Parthian Wars will embroil these ancient empires until the third century.

The Middle East: 129–118 BCE

The Seleucid Collapse and Parthian Ascendancy

The period from 129 to 118 BCE signifies a crucial turning point in Middle Eastern history, characterized by the near-complete collapse of the Seleucid Empire and the definitive rise of Parthian power.

In 129 BCE, the Parthians decisively repel the last major Seleucid attempt at reconquest in a significant battle at Ecbatana, where Seleucid king Antiochus VII is killed. This crushing defeat effectively signals the end of Greco-Macedonian influence east of the Euphrates and severely weakens the already fragile Seleucid state. Following this loss, the Seleucid Empire shrinks dramatically, essentially reduced to a rump state consisting primarily of Antioch and its immediate surroundings.

The Seleucid realm plunges into internal chaos, with multiple claimants battling for control and neighboring states steadily encroaching upon its diminished borders. The return of former king Demetrius II from Parthian captivity only exacerbates the instability. During his second reign, Demetrius holds limited territory and is assassinated around four years later, highlighting the Empire's rapid decline into internal fragmentation.

This era also witnesses profound cultural exchanges between the Greco-Macedonian west and the Persian-influenced east. Greek thought and practices deeply permeate eastern regions, while Persian and Indian sciences, literature, and architectural influences gradually spread westward, leaving enduring legacies.

Significantly, Parthia's westward territorial expansion during these years sets the stage for inevitable conflicts with the rising power of Rome. The resulting Roman–Parthian rivalry will dominate geopolitical dynamics in the Middle East for several centuries.

Thus, the period from 129 to 118 BCE marks the decisive demise of Seleucid dominance, solidifies Parthian power, and initiates a lasting geopolitical rivalry between Parthia and Rome, profoundly reshaping the Middle East.

The Parthians drive back the last Seleucid counterattack in 129 BCE, a turning point in the history of the eastern Mediterranean: Greco-Macedonian domination receives a decisive blow, which it will survive for only forty-six more years.

The loss of their king in the battle of Ecbatana together with so much territory sends the already enfeebled Seleucid empire into a decline from which it can never recover.

The Empire becomes a rump state that consists of little more than Antioch and the surrounding lands.

The only reason the Seleucid Empire continues to exist is because the Parthians see it as a useful buffer against the Roman Empire.

Antiochus leaves five children by his queen.

Syria lapses into civil war, with all hopes of empire gone.

Demetrius II returns to Syria after his release form captivity, but during his second reign, he controls only part of the kingdom, and is assassinated about four years later.

Neighboring states begin to gnaw constantly at the edges of the weak and divided kingdom.