- "Now, there's this about cynicism, Sergeant. It's the universe's most supine moral position. Real comfortable. If nothing can be done, then you're not some kind of shit for not doing it, and you can lie there and stink to yourself in perfect peace."
- ―Miles convinces Oliver to return to the battle[src]
Sergeant Oliver was a soldier for Marilac who fought under Colonel Guy Tremont at Fallow Core until it fell to the Cetagandans. When he was taken prisoner, he and the other Fallow Core fighters were sent to Dagoola IV Top Security Prison Camp 3, where they became subjects of a cruel Cetagandan experiment in mass psychology.
When Miles Vorkosigan showed up in the camp disguised as a fellow Marilacan prisoner, Sergeant Oliver was one of the first people he convinced to join with him; he was later one of the two that Miles picked as the new leaders of Marilac's resistance when he freed them from the prison.