Smith was pushed farther north into what is now Montana, guarding the upper stretches of the trail.

Building Fort Phil Kearny was a major undertaking.

The post eventually included a stockade more than 600 feet long and nearly 500 feet wide, with blockhouses at two corners.

The construction required enormous quantities of timber, which had to be cut in the nearby forests and hauled to the construction site — a task that required work parties to leave the fort’s protection on a daily basis.

Those work parties became Red Cloud’s preferred target.