The Pass 29 December 1959

In "The Pass", 29 December 1959, Slim and Jess are members of the US Army Reserve and are activated to serve as scouts.

General Howard sends Slim and a Sergeant Coffey with several men with a load that includes many boxes of dynamite on a mission to cause an avalanche that will block a pass, preventing the Cheyenne from moving north through that pass and joining with the Sioux to overwhelm the column of Colonel Custer with Jess as a scout.

Since Colonel Custer of the 7th Cavalry is alive, the date must be before June 25, 1876. Since "The Pass" happens in winter, and there is snow in many scenes, it must be be in the winter of 1875-'76, or the winter of 1874-'75, or the winter of 1873-'74, etc., back to the earliest possible date for the episode.

Alfred Nobel patented dynamite in England 7 May 1867 and in Sweden 19 October 1867. It was originally called Nobel's Blasting Powder and I don't know when it was named dynamite.

So the possible winters that "The Pass" could happen during include 1867-'68, 1868-'69, 1869-'70, 1870-'71, 1871-'72, 1872-'73, 1873-'74, 1874-'75, or 1875-'76.

Another constraint on the date of "The Pass" is that all the episodes with Andy Sherman must happen during a comparatively short period since Andy is a growing boy who doesn't grow much during the period he is in the series. So if Andy is seen in "The Pass", "The Pass" can not be more that at most one or two years before or after the date range of any other episode with Andy. I didn't see all of "The Pass" on February 22, 2019 so I didn't see if Andy was in any part of the episode.

Another clue to the date of "The Pass " is it happens when a major general Howard is in command of the area that includes Wyoming. The smallest territorial military administrative units are districts, which in those days would contain one or more forts, and sometimes covered an entire state or territory. A number of districts would be grouped together in a military department which usually covered several states and/or territories. And a number of departments would form a (territorial) military division, the commander of which was directly subordinate to the commanding general.

In those days the various military districts in Wyoming were part of the Department of the Platte (1865-1898) which contained Utah, part of Idaho, Wyoming, Nebraska, & Iowa. The Department of the Platte was commanded by General Oliver Otis Howard from September 5, 1882 to March 6, 1884, and again from October 25, 1884 to April 28, 1886 - both times after Custer was dead.

The Military Division of the Missouri created in 1865 Contained all the plains region west of the Mississippi river including the Department of the Platte. Its commanders during the Indian Wars included General John Pope, General William T. Sherman, General Philip Sheridan (1869-1883), etc., and never a General Howard.

"The Pass" opens with the burial of many soldiers of Company B, First US Cavalry killed in a Sioux ambush. The first US Cavalry was stationed in the west coast states and territories from 1865-1884, and then transferred to the plains - again after Custer was dead.

The United States army Reserve was created after World War One. Thus Slim and Jess could not have been reservists and called to active duty in the 1860s, 1870s, or 1880s. But the generation who were of military age during WWII and Korea that included many of the creators of 1950s television and its adult viewers were very familiar with the army reserve and no doubt found it easy to imagine that system had existed during the Indian Wars.