One of the primary goals of the
Powder River Expedition of 1865 was to construct a fort on the
Powder River in
Montana Territory or
Dakota Territory. The expedition's left, or western column of about 650 men under the command of
Colonel James H. Kidd of the
6th Michigan Cavalry, accompanied by the expedition's overall commander
Brigadier General Patrick E. Connor, set out from
Fort Laramie,
Dakota Territory on August 1, 1865. Army units with the column included Companies L, and M, of the
2nd California Volunteer Cavalry Regiment, four Companies of the
6th Michigan Volunteer Cavalry Regiment, Companies E, and K, of the
11th Ohio Volunteer Cavalry Regiment, Company F, of the
7th Iowa Volunteer Cavalry Regiment, a detachment of the
United States Signal Corps, the
Pawnee Scouts and a section of two
Model 1841 Mountain Howitzers manned by 14 soldiers of the
2nd Missouri Volunteer Light Artillery Regiment. On August 15, 1865, Colonel Kidd's column selected the site of the fort on a bluff above the Powder River near the crossing of the
Bozeman Trail. Construction began the same day by the four companies of the
6th Michigan Cavalry that had recently been transferred from the
Army of the Potomac in
Virginia. The new post was named Fort Connor in honor of Brigadier General
Patrick Edward Connor, the overall commander of the
Powder River Expedition. That month, Fort Connor was the jumping-off point for the soldiers that fought at the
Battle of the Tongue River on August 29, 1865, in present-day
Sheridan County, Wyoming. The left, right, and center columns of the Powder River Expedition all finally rendezvoused at Fort Connor on September 25, 1865. Army units that arrived in September included companies from the 2nd Missouri Volunteer Light Artillery Regiment,
12th Missouri Volunteer Cavalry Regiment,
15th Kansas Volunteer Cavalry Regiment, and the
16th Kansas Volunteer Cavalry Regiment, along with a second detachment of the U.S. Signal Corps. Most of these men marched south to
Fort Laramie in October, 1865 to be mustered out of the army, leaving the four companies of Michigan cavalry under Colonel James H. Kidd to garrison the fort. == Renaming ==