282 BCE - 263 BCE: Philetaerus, founder of the Attalid dynasty, governs Pergamon.
263 BCE - 241 BCE: Reign of Eumenes I at Pergamon
262 BCE: Eumenes rebels and wins against the Seleucid Antiochos I. Beginning of the Pergamon Empire.
241 BCE - 197 BCE: Reign of Attalus I at Pergamon.
237 BCE - 241 BCE: Attalus I of Pergamon defeats the Galatians at the headwaters of the Caioc River.
218 BCE: The Aegosages Celts enter Anatolia under Attalos of Pergamon.
197 BCE - 159 BCE: Reign of Eumenes II at Pergamon.
189 BCE: The treaty of Apameea Kibotos. Peace and alliance is established between the Seleucid Kingdom and Rome joined by her allies, such as Pergamon and Rhodes. The Seleucids have to evacuate all the land and the cities from Asia Minor and to pay a huge war indemnity.
188 BCE: Maximum extent of the Pergamon Empire after Apamea peace.
187 BCE - 183 BCE: The Attalids of Pergamon are at war with Bithynia.
183 BCE - 179 BCE: The Attalids of Pergamon are at war with Pontius.
160 BCE - 138 BCE: Reign of Attalus II at Pergamon.
138 BCE - 133 BCE: Reign of Attalus III at Pergamon.
133 BCE: Attalus III, the last king of Pergamon, bequeathes the whole of Pergamon to Rome.