 FACT: Captain Parmenter talks about going to a command course at  Fort Riley, Kansas being given by General George Armstrong Custer.  If the show was set in the period from 1865 to 1867, then Custer  would no longer have been a General. After the Civil War ended,  Custer was reverted back to the rank he had held before the Battle  of Gettysburg, which was Captain. His Volunteer Commission as a  General expired on January 31, 1866. So, in reality, Captain Wilton  Parmenter would have been senior to him. Like many officers in the  Union army, Custers rank of General was a brevet rank.