Demetrius I of Macedon

Demetrius I (/dɪˈmiːtriəs/; Ancient Greek: Δημήτριος; 337–283 BC), called Poliorcetes (/ˌpɒliɔːrˈsiːtiːz/; Greek: Πολιορκητής, "The Besieger"), was a Macedonian Greek nobleman and military leader who became king of Macedon between 294–288 BC. A member of the Antigonid dynasty, he was the son of its founder, Antigonus I Monophthalmus and his wife Stratonice, as well as the first member of the family to rule Macedon in Hellenistic Greece.

In 307 BC, Demetrius successfully ousted Cassander's governor of Athens and after defeating Ptolemy I at the Battle of Salamis (306 BC) he gave his father the title of basileus ("king") over a land spanning from the Aegean Sea to the Middle East. He acquired the title Poliorcetes ("the besieger") after the unsuccessful siege of Rhodes in 305. While Antigonus I and Demetrius planned a revival of the Hellenic League with themselves as dual hegemons, a coalition of the diadochi; Cassander, Seleucus I, Ptolemy I, and Lysimachus defeated the two at the Battle of Ipsus in 301 BC, in which Antigonus I was killed and the Asian territory of his empire was lost. In 294, Demetrius managed to successfully seize control of Athens and establish himself as king of Macedon. He ruled until 288 when he was eventually driven out by Pyrrhus and Lysimachus and later surrendered to Seleucus I in Cilicia, dying there in 283. After a long period of instability, Demetrius' son, Antigonus II Gonatas, managed to solidify the dynasty in the kingdom and establish its hegemony over much of Hellenistic Greece.