The fortification was genuinely impressive by frontier standards: a stockade of substantial logs, blockhouses at two corners, barracks for the soldiers, officers’ quarters, a magazine, a hospital, workshops, and stables for the horses and mules that were essential to the post’s operation.

It was not temporary — it was built to last.

The cost of supplying and manning the three forts over two years, including the casualties of the engagements and the expenditures on military operations, was substantial.

Precise figures are difficult to compile from the period’s records, but the overall cost of the Bozeman Trail campaign to the Army and to the Indian Bureau — which was responsible for the treaty negotiations and the annuity payments that were part of U.S.

Indian policy — ran into millions of dollars, a significant sum for the post-Civil War government.