Used with permission from: http://kart-hadasht.co.uk/anc/sel.php
Seleucus IV Philopator: 187-175 BC
Though Seleucus' rule is an uneventful period of recovery, the heavy taxation needed to pay the indemnity to Rome doesn't help Seleucid popularity. Rome insists that Antiochus the younger son of Antiochus III be replaced by Demetrius, the eldest son of Seleucus and his heir. Antiochus takes his time returning home and ends up in Athens where he (successfully) runs for election.
Seleucus is assassinated by his first minister Heliodorus.
Antiochus IV Epiphanes 175-164 BC
Antiochus, on hearing of his brother Seleucus' murder, leaves Athens and sails for Pergamon. Then with Pergamese help he seizes power in Syria. The claim of Demetrius, the eldest son of Seleucus and still a hostage in Rome, is quietly forgotten.
In 173 an anti Seleucid faction comes to power in Egypt which is determined to regain Coele Syria. The invasion (170/169) is defeated and Antiochus invades Egypt capturing Pelusium and Ptolomy Philometor the King. Alexandria proclaims Ptolomy Euergetes Philometor's brother as King and prepares to fight on. Antiochus does a deal with Ptolomy Philometor and leaves Egypt divided with Philometor ruling from Memphis. The two Ptolomy brothers however agree to rule jointly so Antiochus again invades only to be blocked by Roman ambassadors just as Antiochus is approaching Alexandria(168). Antiochus pulls out of Egypt. In Jerusalem Antiochus intervenes rather brutally in the faction fighting that has troubled the client Jewish state. This helped provoke the rebellion of the Maccabees and gained Antiochus very bad press and to the writer of Daniel becomes virtually the anti-christ. In 165 he headed East but died of illness the following year.
Antiochus V Eupator 164-162 BC
Lysias acts as regent for the nine year old son of Antiochus. The Jewish revolt smolders on. In 163 Octavius an envoy sent from Rome to ensure the destruction of ships built in excess of treaty limits is assassinated much to the horror of Lysias but the envoys flee as a result of anti Roman feeling in Syria.
Demetrius I Sotor 162-150 BC
Demetrius, the son of Seleucus and his true heir, escapes from Rome, lands at Tripolis and proclaims himself King. Lysias' rule collapses and the mutinous troops murder Antiochus V at Demetrius' request: "let me not see their faces". The histories tell us that the Atiochenes soon become disillusioned with the dour Demetrius but it is enemies abroad that bring him down. After a botched attempt to secure his own claimant on the throne of Capidocia Pergamum and Ptolemaic Egypt combine against him backing Alexander Balas, the supposed son of Antiochus Epiphanes. Alexander establishes a base at Ptolemais and Demetrius is killed in the fighting.
Alexander Balas 150-146 BC
Alexander is married off to Cleopatra Thea, the daughter of Ptolemy Philometor (King of Egypt). Three years pass while Balas enjoys his Kingdom but now Demetrius ( all of 14 years old), son of Demetrius Sotor arrives with the backing of a bunch of Cretan mercenaries led by Lasthenes. Ptolomy comes to Ballas' aid (and just happens to spend time capturing the cities of Palestine that Egypt has always considered it's inheritance). Ballas, who can do without such 'help', attempts to assassinate Ptolomy (or is Ballas being framed to cover Ptolomys betrayal?). Ballas flees to Cilicia and the Atiochenes proclaim Ptolomy as King. Knowing that Rome will not permit this he persuades Antioch to accept Demetrius who marries Cleopatra Thea.
Demetrius II Nicator (part 1) 146-140 BC
Balas makes one last play but is defeated and killed but Ptolomy is mortally wounded. Lasthenes gets Demetrius to order a massacre of the leaderless Ptolomid army. The Jewish leader Johnathan is bought off by a grant of autonomy. Lasthenes knowing that the native Greek soldiery is a threat to his position orders them to be disarmed. Antioch rises against Demetrius but the rising is brutally put down by the Cretan mercenaries and Jewish troops sent by Johnathan. Antioch is looted and with a large part of the city destroyed by fire is cowed but nemesis is at hand.
Diodotus proclaims the son of Balas, Antiochus, as King. Antioch and most of inland Syria joins him. The civil war drags on and within three years Antiochus has died of "illness" and Diodotus has proclaimed himself King as Tryphon. In an attempt to break the deadlock Demetrius by passes Tryphon and enters Mesopotamia in an attempt to recapture it from the Pathians. Though initially successful he is soon captured by the Pathians.
Antiochus VII Sidetes 139-129 BC
Antiochus, Demetrius's younger brother is proclaimed King and maries (you've guessed it) Cleopatra Thea. He defeats Tryphon. He then moves on Jerusalem and ends (for the moment) Jewish independence. By 130 BC he is ready to take on Parthia and reconquers Babylonia. The desperate Parthian King releases Demetrius Nicator (bad move) and stirs revolt amongst Antiochs's new conquests who do not find Seleucid taxes to their liking (good move). Antiochus is completely wrong footed by the revolt and is caught, heavily outnumbered, by the Parthian main army and killed. The Pathian king immediately sends cavalry to recapture Demetrius but too late.
Demetrius II Nicator (part 2) 129-125 BC
Demetrius arrives in Syria at the same time as news of Antiochu's death and regains both his throne and his wife Cleopatra Thea. (Cleopatra has however taken the precaution to send her son by Sidetes, Antiochus, to Cyzicus in Asia Minor.) After a botched invasion of Egypt by Demetruius, Ptolomy Euergetes discovers a son of Balas known as Antiochus Zabinas. (Is he really the son of Balas? Does anyone care?) Zabinas quickly gains control of the inland region held by Tryphon and Syria is again divided. Finally Demetrius is defeated outside Damascus and retreats to Ptolemais only to find the gates closed against him by his wife Cleopatra. He takes a ship and is killed on Cleopatra's orders.
Cleopatra Thea (Antiochus VIII Grypus)125-121 BC
Cleopatra decides to rule in her own right and Selecus's the eldest son of Demetrius is killed when he is foolish enough to put forward his claim. As a sop to those unaccustomed to female rule she associates her rule with her son the pliable Antiochus Grypus (hooknosed). Zabinas is defeated by Grypus. Antiochus proves to be less an less pliable. Things come to a head when Cleopatra offers a cup of wine to Antiochus when he has returned from the hunt. As this is most definitely not her habit Antiochus has a hunch this is not maternal concern. He insists she drink the wine. She drinks. She dies.
Antiochus VIII Grypus 121-96 BC
Grypus (ie hook nose) demonstrates the superiority of male rule by spending his time feasting at Daphne and writing verses on poisonous snakes.
In 116 Antiochus, the son of Sidetes who Cleopatra Thea sent to Cyzicus to save him from Demetrius, arrives in Syria to make a play for the throne. This is helped by the arrival of Cleopatra a Ptolomid princess who decided to go adventuring after she fell out with her mother the Queen and who has acquired an army on the way. Cleopatra marries Antiochus (known as Cyzicenus). As Cyzicenus's half brother Grypus's wife is Tryphaena who is Cleopatra's sister this gives the civil war an extra incestuous twist. Antioch as usual is held by the rebel forces of Cyzicenus. Grypus moves on Antioch while Cyzicenus has left it in the hands of Cleopatra. Antioch falls. Tryphaena demands the death of Cleopatra. Gryphus refuses. Convinced this is a sign of a secret desire on the part of Grypus for Cleopatra, she sends troops to the sanctuary in Daphne where Cleopatra has taken refuge. Cleopatra hangs on to the image of Artemis with such desperation that the soldiers cannot break her hold so instead the cut through her wrists. Cleopatra's death is soon avenged when Tryphaena falls into the hands of Cyzicenus and is executed.
Disintergration 96-83 BC
Grypus is murdered by his minister Heracleon who proclaims himself King. However Grypus's eldest son, Seleucus, inherits most of his father realm with Heracleon retaining a small principality round Beroea. Seleucus marches on Cyzicenus and kills him in battle. Cyzicenus' son Antiochus Eusebes is proclaimed King and in turn defeats Seleucus who flees to Cilicea and establishes himself in Mopsuhestia. The people of Mopsuhestia, unable to support a King's lifestyle rebel and Seleucus dies in his burning palace. Philip and Antiochus, the brothers of Seleucus avenge themselves on Mopsuhestia and then march on Antioch where they are defeated and Antiochus rides his horse into the Orontes and is drowned. A fourth son of Grypus, Demetrius arrives, backed by Ptolomid troops, and establishes himself in Damascus. What follows is a period of confused fighting that the historical records do not do justice. Seleucid "Kings" are now little more than local barons.
Tigranes of Armena 83-69 BC
Tigranes moves into Syria. A faction in Antioch invites him in. Magadates, Tigranes' governor sits in the Palace in Antioch. The Syrians are soon unhappy with Armenian rule but Tigranes is not so easy to get rid of as a Seleucid prince. Only a couple of isolated cities still recognize Seleucid rule (notably Seleucia). But Tigranes is foolish enough to annoy the Romans and Tigranes is defeated by Lucullus
Rome takes over
A son of Antiochus Eusebes establishes himself in Antioch with Lucullus' approval but soon being challenged Philip son of Philip, son of Grypus. Both are however little more than tools in the ambitions of minor Arab chieftains. Pompeus arrives and decides to establish Syria as a Roman Province.
Why did the Seleucid Empire self-destruct?
The Romans did not conquer the Seleucid Empire. After the defeat at Magnesia the empire was still strong. The Pergamese and Ptolomids stirred things up for their own ends but essentially the Seleucids destroyed themselves in bitter and, by the end, continuous civil war. Why?
Bevan's explanation is folly. The Seleucids had the bad luck to be produce a bunch of tyrants who squandered the fine empire they inherited from illustrious ancestors. Peter Green's explanation goes deeper but is essentially the same (though unlike Bevan he regards the Empire as flawed from the start).
"If the 'degenerate' has any meaning at all the later Seleucids and Ptolomids were degenerate: selfish, greedy, murderous, weak, stupid, vicious, sensual, vengeful....
In both dynasties we also find the cumulative effect of centuries of ruthless exploitation: a foreign elite, with no long term economic insight, aiming at little more than the immediate profits and dynastic self perpetuation, backed (for their own ends) by shrewd local and foreign businessmen and always able to count on a mercenary army when resentment reached boiling point."
Peter Green: Alexander to Actium p555