Ptolemy VI Philometor is in 145 BCE drawn into a battle in which Demetrius' son defeats Balas in his last desperate attempt to regain his throne.

During the battle, Ptolemy had fallen from his horse and fractured his skull, dying a few days later.

The Egyptian troops march home, leaderless and disillusioned.

Balas had meanwhile fled for refuge to a Nabataean prince, who murders him and sends his head to Ptolemy's court.

The Seleucid prince takes the throne as Demetrius II Nicator (Greek “Victor”).

New troubles soon arise, however.

The pillaging of the Cretan soldiers under Lasthenes cause the Antiochenians to rise in rebellion, and only after terrible massacres can order be restored.

In opposition, Diodotus Tryphon, or Trypho, a general of the Syrian army, promotes the claims of Balas' young son by Cleopatra Thea, Antiochus VI Epiphanes Dionysius.

Demetrius proves unable to retake the capital, instead …

…establishing himself in Seleucia.

The Jewish forces under the High Priest Jonathan have behaved too boldly for the comfort of the Syrian regent Diodotus, who in 143 leads an army to Judea and invites Jonathan to Scythopolis for a friendly conference, persuading him to dismiss his army of forty thousand men and promising to give him Ptolemais and other fortresses.

Jonathan falls into the trap, taking with him to Ptolemais one thousand men, all of whom are slain; he himself is taken prisoner.

Diodotus, intending to cow the Jews, is about to enter Judea when he is confronted by Jonathan’s brother, Simon, ready for battle.

Simon, who has quietly and loyally served under his other brothers, all now dead, is a man of character and prudence as well as a born leader.

Diodotus, avoiding an engagement, demands one hundred talents and Jonathan's two sons as hostages, in return for which he promises to liberate Jonathan.

Although Simon does not trust Diodotus Tryphon, he complies with the request in order that he might not be accused of the death of his brother.

However, Diodotus, angry that Simon has everywhere blocked his way and that he can accomplish nothing, executes Jonathan; nothing is known of his two captive sons.

The Hasmonean revolt, waged by the orthodox Jews of southern Syria against Seleucid rule over Judah, has been largely successful.

Simon secures from Diodotus, in the name of the general’s ward, Antiochus VI, exemption from taxation for the Jews and the right to issue his own coins.

The Jews pass a decree in Simon's honor, granting the right of permanent incumbency to Simon and to his successors, until "an accredited prophet" should arise.

It is thus during Simon's reign that the rule of the priest-prince will be transformed into a secular hereditary rule.

The internal situation in the Seleucid domains is so convoluted, and the rebel general and Seleucid pretender Diodotus so eager to gain allies, that he recognizes Hasmonean rule over Judea in exchange for little gain beyond a minor tribute of one hundred talents.

Simon Thassi in 142-141 forces the surrender of the Syrian garrison on the Akra, which apparently had remained loyal to Seleucid king Demetrius II Nicator, and the Jews pass a decree in Simon’s honor, granting the right of permanent incumbency to him and to his successors, until “an accredited prophet” should arise (the Hasmoneans claim no descent from the Davidic line, who had provided the hereditary kings of ancient Judah).

It is thus in Simon's reign that the rule of the priest-prince is transformed into a secular hereditary rule.

Diodotus recognizes this, granting Simon the right to issue his own coins.

Several Jewish armies now march against Diodotus' rival Demetrius and opposing cities.

The child Antiochus VI does not actually rule in Syria.

Either already in 145 or in early 144 BCE he had been nominated by the general Diodotus Tryphon as heir to the throne in opposition to Demetrius II, and remains the general's tool.

The young king dies in about 142/41 BCE.

While some ancient authors make Diodotus Tryphon responsible for the death of the king, others write that he died during a surgery.

Diodotus seizes power in Coele-Syria where the rival Seleucid king, Demetrius II Nicator, is unpopular for his oppressive treatment of the Jews. (Strictly speaking, Coele, or 'hollow', Syria, the region of southern Syria disputed between the Seleucid dynasty and the Ptolemaic dynasty, is the Beqaa Valley of Lebanon, but it is often used to cover the entire area south of the river Eleutherus including Judea.)

The division of the kingdom between the legitimate Seleucid heir and the usurper in Antioch persists.

Simon, on his own initiative, has brought peace and security to Jerusalem, and formalized what Judas had begun, the establishment of a theocracy, something not found in any biblical text.

He soon becomes independent of the Seleucids as high priest, ruler, and ethnarch of Judaea; the offices are hereditary, and Simon thus becomes the first of the Hasmonean dynasty.

Judaean ambassadors to Rome In 139 BCE return with a senatorial decree recognizing the independence of the Jewish state and commending the Jewish people to the friendship of all kingdoms in the East within the Roman sphere of influence.

Simon thus acquires the status of a recognized secular ruler; the year of his assumption of rule is regarded as the first of a new era, and official documents are dated in his name and by his regnal year.

Scipio Aemilianus Africanus Minor, the Roman hero of the Third Punic War, is posted as an ambassador to eastern kingdoms in 140—139 BCE.

Meanwhile, Rome’s praetor (civil administrator) in 139 charges the Jews of the city with attempting to contaminate Roman morals with their religion, presumably an allusion to proselytism.