Complex sentence: Despite Roman attempts to keep the peace, Pharnaces fought against Eumenes of Pergamon and Ariarathes of Cappadocia, while he was initially successful, it seems he was overmatched by 179 when he was forced to sign a treaty.
Split into simpler sentences: Despite Roman attempts to keep the peace, Pharnaces fought against Eumenes of Pergamon and Ariarathes of Cappadocia. While initially successful, it seems he was overmatched by 179 when he was forced to sign a treaty.