Attalus I, surnamed Soter (269 BCE – 197 BCE) rules Pergamon, an Ionian Greek polis (what is now Bergama, Turkey), first as dynast, later as king, from 241 BCE to 197 BCE.
He is the second cousin and the adoptive son of Eumenes I, whom he succeeds, and is the first of the Attalid dynasty to assume the title of king in 238 BCE.
He is the son of Attalus and his wife Antiochis.
Attalus wins an important victory over the Galatians, newly arrived Celtic tribes from Thrace, who have been, for more than a generation, plundering and exacting tribute throughout most of Asia Minor without any serious check.
This victory, celebrated by the triumphal monument at Pergamon (famous for its Dying Gaul) and the liberation from the Gallic "terror" which it represents, earns for Attalus the name of "Soter", and the title of "king".
A courageous and capable general and loyal ally of Rome, he plays a significant role in the first and second Macedonian Wars, waged against Philip V of Macedon.
He conducts numerous naval operations, harassing Macedonian interests throughout the Aegean, winning honors, collecting spoils, and gaining for Pergamon possession of the Greek islands of Aegina during the first war, and Andros during the second, twice narrowly escaping capture at the hands of Philip.
Attalus is a protector of the Greek cities of Anatolia and views himself as the champion of Greeks against barbarians.
During his reign he establishes Pergamon as a considerable power in the Greek East.
He dies in 197 BCE, shortly before the end of the second war, at the age of 72, having suffered an apparent stroke while addressing a Boeotian war council some months before.
He had enjoyed a famously happy domestic life, shared with his wife and four sons.
