Complex sentence: As the insurrection ended and the US gave amnesties to most of their opponents a substantial reward was offered for Fagen, who as a US serviceman who had changed sides was considered by the US as a traitor.
Split into simpler sentences: As the insurrection ended the US gave amnesties to most of their opponents. A substantial reward was offered for Fagen, who as a US serviceman who had changed sides was considered by the US as a traitor.