Pergamon
Pergamon lies on the north edge of the Caicus plain in the historic region of Mysia in the northwest of Turkey. The Caicus river breaks through the surrounding mountains and hills at this point and flows in a wide arc to the southwest. At the foot of the mountain range to the north, between the rivers Selinus and Cetius, there is the massif of Pergamon which rises 335 metres above sea level. The site is only 26 km from the sea, but the Caicus plain is not open to the sea, since the way is blocked by the Karadağ massif. As a result, the area has a strongly inland character. In Hellenistic times, the town of Elaia at the mouth of the Caicus served as the port of Pergamon. The climate is Mediterranean with a dry period from May to August, as is common along the west coast of Asia Minor.
Pergamon Altar
The Pergamene kingdom founded by Philetaerus at the beginning of the 3rd century BC was initially part of the Hellenistic Seleucid empire. Attalus I, successor and nephew of Eumenes I, was the first to achieve full independence for the territory and proclaimed himself king after his victory over the Celtic Galatians in 228 BC. This victory over the Galatians, a threat to the Pergamene kingdom, secured his power, which he then attempted to consolidate. With conquests in Asia Minor at the expense of the weakened Seleucids he could briefly increase the size of his kingdom. A Seleucid counteroffensive under Antiochos III reached the gates of Pergamon but could not put an end to Pergamene independence. Since the Seleucids were becoming stronger in the east, Attalus turned his attention westward to Greece and was able to occupy almost all of Euboea. His son, Eumenes II, further limited the influence of the Galatians and ruled alongside his brother Attalus II, who succeeded him. In 188 BC, Eumenes II was able to create the Treaty of Apamea as an ally of Rome, thus reducing the influence of the Seleucids in Asia Minor. The Attalids were thus an emerging power with the desire to demonstrate their importance to the outside world through the construction of imposing buildings.