The Union Army is a group of Hosts based on the real Union Army that was active during the Civil War.
- Wyatt - backstory
- Teddy Flood - backstory
- Peter Abernathy - backstory
- Branding Soldier
- Wagon driver
- Union Soldier
- Union Scout
Some hosts dressed and equipped as Union Army soldiers (set to Pause Mode), are seen among the assembled host characters during Lee Sizemore's pitch for his latest narrative concept, Odyssey on Red River. The sample of the soldier hosts intended to appear in the new narrative includes an officer and a common soldier. They have no speaking roles.
Doctor Ford decides to give Teddy Flood a new, proper backstory. Teddy's newly acquired memories reflect this. He recalls being a Union soldier once, before returning to civilian life and becoming a bounty hunter. While camped in the town of Escalante, a rebellion broke out among some of the Union soldiers, resulting in the murder of a Union general and the massacre of many of the troops on the town's main street. Teddy participated in some of the fighting (noting that for a moment, "he felt as if he was possessed by the devil"), and witnessed the infamous Wyatt killing the general and ruthlessly gun down many of their fellow soldiers. The slovenly Wyatt is shown wearing a uniform with two stripes (denoting a corporal), but Teddy claims Wyatt was a sergeant (this is a possible hint at the false nature of Teddy's memories, or Teddy misremembering).
A child from a group of Ghost Nation members visiting Sweetwater accidentally drops a strange doll. Maeve picks up the doll from the street, returns it to the child and asks what the doll means. A Union soldier standing nearby mentions the doll's relation to native legends.
A small Union garrison is camped in front of Pariah.
William, Logan, Dolores Abernathy and Slim Miller are tasked by Lawrence to carry out a heist on a Union covered wagon, carrying a secret cache of jars containing nitroglycerine. The four ambush the wagon and get into a tussle with its Union crew, including the wagon driver.
Teddy Flood and the Man in Black are captured by Union soldiers and held as prisoners in a Union army camp, tied to the wheels of a wagon. Teddy managed to break free and use a wagon-mounted Gatling Gun to eliminate the attacking guards at the camp, allowing him and MiB to escape.
- Union Army camp - A Union Army base of operations.