Sean Edmiston was a mechanic and engineer who modified vehicles for special conditions (such as extreme temperatures). He was one of the supervisors of the team that maintained Rogue Squadron's snowspeeders on Hoth. After the Battle of Hoth, he was decorated for bravery and valor, and promoted to Captain, after which he took a position on Colonel Derlin's advisory staff. He retired as a Major shortly after Palpatines' death.