Seleucus III personally leads an army across the Taurus Mountains.

He is assassinated, however, in Phrygia.

After the assassination of Seleucus, his cousin Achaeus, who had accompanied Ceraunus on this expedition against Attalus, revenges his death; and though he might easily have assumed the royal power, he remains faithful to the family of Seleucus.

Antiochus appoints Achaeus to the command of all Asia Minor on the western side of the Taurus mountains.

Achaeus recovers all the districts which Attalus had gained for the Seleucids once more; but being falsely accused by Hermeias of intending to revolt, he does so in self-defense, assumes the title of king, and rules over the whole of Asia on the western side of the Taurus.

Diodotus II—accused, it is thought, of treason to Hellenism through his alliance with the nomads—loses his throne around 230 or 223 BCE to a usurper, his brother-in-law Euthydemus I, founder of the Greco-Bactrian Euthydemid dynasty (Polybius, 11.34, 2).

Doson fails to pierce Cleomenes' lines near Corinth in 224 BCE, but …

…a revolt against Cleomenes at Argos puts the Spartans on the defensive.

The Qin army led by Wang Ben, the son of Wang Jian, invades Liaodong in 222 BCE and destroys Yan's remaining forces at Liadong.

King Xi of Yan is captured alive; his fate is not known.

The former territories of Yan are partitioned and reorganized to form the Qin Empire's Yuyang, Beiping, Liaoxi and Liaodong prefectures.

Yan is the third last state to fall, and with its destruction the fates of the remaining two kingdoms are sealed.

Molon rebels in 222 BCE and assumes the title of king.

Ptolemy III Euergetes, Macedonian ruler of Egypt, had sent aid to Rhodes after earthquakes in 226-225 devastated the island.

Avoiding involvement in the wars that have continued to plague Syria and Macedonia, he had refrained also from subsidizing the schemes of the Spartan king Cleomenes against Macedonia, though he grants him asylum in 222, his policy being to maintain an equilibrium of power, guaranteeing the safety of his own territory.

The early Ptolemies have not disturbed the religion or the customs of the Egyptians, and indeed built magnificent new temples for the Egyptian gods and soon adopted the outward display of the Pharaohs of old.

Thousands of Greek veterans during the reign of Ptolemies II and III have been rewarded with grants of farm lands, and Greeks have been planted in colonies and garrisons or settled themselves in the villages throughout the country.

Upper Egypt, farthest from the center of government, is less immediately affected, though Ptolemy I had established the Greek colony of Ptolemais Hermiou to be its capital, but within a century Greek influence had spread through the country and intermarriage had produced a large Greco-Egyptian educated class.

The Greeks nevertheless always remain a privileged minority in Ptolemaic Egypt.

They live under Greek law, receive a Greek education, are tried in Greek courts, and are citizens of Greek cities, just as they had been in Greece.

The Egyptians are rarely admitted to the higher levels of Greek culture, in which most Egyptians are in any case not interested.

A large factor in the prosperity of the Ptolemaic Empire in Egypt is the exploitation of the region's resources, both natural and human.

The Nile valley is rich with resources available at the Ptolemies' disposal, and there is a large Egyptian population available to be utilized for labor.

Two of the most valuable resources for the Greeks in Ptolemaic Egypt are grain and papyrus, the writing paper of the time period.

After declaring his seventeen-year-old son Ptolemy IV Philopator (Greek: Loving His Father) his successor, Ptolemy dies in 221, leaving Egypt at the peak of its political power and internally stable and prosperous.

The new king, weak and easily influenced, has his mother, brother, and others at the urging of advisors.

Cleomenes plunders Megalopolis, until now a strategic barrier against Sparta, in 223 BCE; however, …

…Doson and a combined force of Achaeans and Macedonians march into Greece and, after defeating Cleomenes at Sellasia (north of Sparta) in the summer of 222, …