Attalus II Philadelphus
References
Table:
Regnal titles

Preceded by

Eumenes II

King of Pergamon
159–138 BC

Succeeded by

Attalus III

Studying the table that covers 'Attalus II Philadelphus' (see 'References'), summarise the highlighted cells in a single sentence and format it within the following JSON object {"answer": "YOUR ANSWER"}.