Following Antipater’s death in 319 BC, Kassander expected to inherit his father’s authority. Instead, the regency was granted to the general Polyperchon. Refusing to accept this decision, Kassander launched a campaign to seize control of Macedon and Greece. Through a series of shifting alliances and military engagements, he gradually secured dominance in the region.

In order to eliminate rival claims to the throne, Kassander imprisoned Alexander’s widow, Roxana, along with her young son, Alexander IV. Around 310/309 BC, both were quietly executed, bringing an end to the Argead royal line that had ruled Macedon for generations. To strengthen his own legitimacy, Kassander married Thessalonike, Alexander’s half-sister, and founded the city of Thessaloniki in her honor.

By 305 BC, the major successors had begun proclaiming themselves kings, and Kassander followed suit, assuming the royal title. His reign was marked more by political consolidation than by grand conquests. He reorganized cities, founded Cassandreia on the site of ancient Potidaea, and maintained Macedonian authority over much of Greece.

This coin was struck during his regency so he used the Argead Dynasty as his imagery placing the posthumous Philip II on his coins. While this coin looks like one of Philip II it is in fact struck only in Philip's name in a time of conflict in the dynasty.

Kassander died in 297 BC, leaving the throne to his sons. Their internal struggles weakened the kingdom, and within a generation the Antigonid dynasty would take control of Macedon. Though often remembered for the ruthless elimination of Alexander’s heirs, Kassander played a crucial role in shaping the political landscape of the early Hellenistic world, transforming Macedon from the center of a vast empire into a regional Hellenistic kingdom.