Major General Grenville M. Dodge orders the Powder River expedition as a punitive campaign against the Sioux, Cheyenne and Arapaho.

It is led by Brigadier General Patrick E. Connor.

Dodge orders Connor to "make vigorous war upon the Indians and punish them so that they will be forced to keep the peace." (Hampton, H.D. "The Powder River Expedition 1865" Montana: The Magazine of Western History, Vol. 14, No. 4 (Autumn 1964)).

The Connor expedition is one of the last Indian war campaigns carried out by U.S Volunteer soldiers.

One of Connor's guides is the legendary frontiersman Jim Bridger, who in the previous year had blazed the Bridger Trail, an alternate route from Wyoming to the gold fields of Montana that avoided the dangerous Bozeman Trail.

Connor's strategy is for three columns of soldiers to march into the Powder River Country.

The "Right Column" is composed of fourteen hundred Missouri soldiers, mostly mounted, led by Colonel Nelson Cole.

It marches from Omaha, Nebraska and is to follow the Loup River in Nebraska westward to the Black Hills and meet up with Connor near the Powder River.

The "Center Column" of six hundred men is commanded by Samuel Walker of the 16th Kansas Cavalry and is to head north from Fort Laramie and traverse the country west of the Black Hills.

The "Left Column" of six hundred and seventy-five men is composed of the 6th Michigan Volunteer Cavalry Regiment under Colonel James H. Kidd, recently transferred from the Civil War battlefields of Virginia.

This command includes ninety-five Pawnee and eighty-four Omaha scouts and a wagon train full of supplies with one hundred and ninety-five civilian teamsters.

General Connor will personally accompany Kidd's column and will move along the Powder River with the goal of establishing a fort near the Bozeman Trail.

All three columns are to unite at the new fort.

Connor's orders to his commanders are, "You will not receive overtures of peace or submission from Indians, but will attack and kill every male Indian over twelve years of age."

Connor's superiors, Generals Pope and Dodge, attempt to countermand this order, but too late, as Connor's expedition has already departed and is out of contact.