In 301 BC Ptolemy I Soter, who four years earlier had crowned himself King of Egypt, exploited events surrounding the Battle of Ipsus to take control of the region.

A decade into his rule, Ptolemy II faced Antiochus I, the Seleucid king who was trying to expand his empire's holdings in Syria and Anatolia.

In addition, his recent marriage to his court-wise sister Arsinoe II of Egypt had stabilized the volatile Egyptian court, allowing Ptolemy to successfully carry out the campaign.

He won major victories over Seleucus in Syria and Anatolia, briefly occupied Antioch and, as a recent cuneiform discovery[1] proves, even reached Babylon.

His domineering mother asked him to grant co-regency to his younger brother, Antiochus Hierax, as well as rule over Seleucid territories in Anatolia.

In exchange for peace in 241 BC, Ptolemy was awarded new territories on the northern coast of Syria, including Seleucia Pieria, the port of Antioch.

The rule of the newly inaugurated Ptolemy IV Philopator (reigned 221–204 BC) began with the murder of queen-mother Berenice II.

Rather than promptly invading Egypt, Antiochus waited in Phoenicia for over a year, consolidating his new territories and listening to diplomatic proposals from the Ptolemaic kingdom.

Ptolemy's victory preserved his control over Coele-Syria, and the weak king declined to advance further into Antiochus' empire, even to retake Seleucia Pieria.

After a brief setback at Gaza, he delivered a crushing blow to the Ptolemies at the Battle of Panium near the head of the River Jordan which earned him the important port of Sidon.

Antiochus completed the subjugation of Coele-Syria in 198 BC and went on to raid Ptolemy's remaining coastal strongholds in Caria and Cilicia.

After losing the Roman-Seleucid War, they were forced to pay a huge indemnity that the Roman Republic imposed on them at the Treaty of Apamea in 188 BC.

Ptolemy V seemed to possibly be intending to raise funds to finance an attempt to reclaim Coele-Syria, but died unexpectedly in 180 BC; in the paranoid atmosphere of the era, many assumed he had been poisoned, perhaps by courtiers who wished to keep the peace and avoid taxes or levies to finance a war, or because they preferred a young king and regent who would be easier to manipulate.

Cleopatra, the regent, favored the peace faction at court, whether because she agreed a war made no sense, or because of lingering loyalties to the Seleucid royal family she descended from.

Eulaeus and Lenaeus, a eunuch and a slave, became the two regents of the young king of Egypt, likely as a compromise between the relevant Egyptian factions who could not bear to see a rival on the throne who might have the backing and lineage to claim it themselves.

While the causes are still not entirely clear, Ptolemaic regents Eulaeus and Lenaeus seem to have instigated the formal declaration of war on Seleucid ruler Antiochus IV Epiphanes.

[4] The Egyptians suffered internal unrest over the poor progress of the war: Eulaeus and Lenaeus were overthrown and replaced by two new regents, Comanus and Cineas.

Antiochus took Ptolemy VI (who was his nephew) under his guardianship, perhaps with the intent of making Egypt a client state subordinate to Seleucid power.

Archaeological records show that even Thebes in the southern part of Egypt were occupied by a foreign army (surely the Seleucids) in October 169 BC.

Antiochus besieged Alexandria but he was unable to cut communications to the city so, in late autumn of 169, he withdrew his army, leaving Ptolemy VI as a rival king in Memphis.

Rome had only just recently defeated the Macedonians at the Battle of Pydna, potentially freeing up armies with which it could credibly threaten the Seleucids.

[6] Antiochus begged to have time to consider but Popilius drew a circle round him in the sand with his cane and told him to decide before he stepped outside it.

A rebel named Dionysus Petrosarapis would attempt to exploit the animosity between the two Ptolemy brothers and start a series of revolts from 168–164 BC.

The Seleucid Empire began to fall to internal disorder in 152 BC as the Romans and Pergamese, seeking to destabilize and weaken Syria, encouraged Alexander Balas to make a hostile claim on the throne against King Demetrius I Soter.

Alexander's allies funded him and hired mercenaries on his behalf, and he was able to gain the loyalty of those of Syria who disliked Demetrius, such as Jewish military leader Jonathan Apphus.

Alexander eventually won the civil war, a diplomatic coup for Ptolemy VI who saw a competent, ambitious, and hostile Seleucid rival in Demetrius replaced by an opportunist in Balas.

As Ptolemy VI marched north, he switched sides and demanded his son-in-law hand over his chief minister on likely faked charges.