The Powder River Expedition may refer to either of two 19th Century military expeditions by the U.S. Army against the Indians of the Wyoming Territory and the Montana Territory.

1865

In 1865, Major General Grenville M. Dodge ordered the first Powder River Expedition as a punitive campaign against the Sioux, Cheyenne and Arapaho for raiding along the Bozeman Trail. It was led by Brigadier General Patrick E. Connor, and is sometimes referred to as the Connor Expedition. One of the guides for Connor's forces was the legendary frontiersman Jim Bridger. The expedition encountered only minor skirmishing until it reached the camp of Arapaho Chief Black Bear along the Tongue River. The Battle of the Tongue River was the only major engagement of the expedition and was a victory for the army. The battle ended Arapaho attacks on the overland trails for a while, but overall, the campaign did little against the Sioux. The fighting in the Powder River Country eventually grew into Red Cloud's War.

1876

In 1876, Brigadier General George Crook led an expedition along the Powder River in concert with the movements of Alfred Terry in Montana and George Custer. Collectively, these movements were known as the North Plains Campaign during the Black Hills War, in which the Powder River Expedition was a small part. The U.S. Army suffered a setback after the Battle of the Powder River when blizzard conditions forced a retirement, but Crook mounted a second larger expedition and fought the Battle of the Rosebud, where he was stopped in southern Montana. Crook's civilian contract surgeon Dr. Valentine McGillycuddy arrived at Little Bighorn battlefield shortly after Custer's defeat, but his main force returned to its supply base on Big Goose Creek, enabling the Lakota and Cheyenne to defeat the U.S. forces in detail.

After the Battle of the Little Bighorn, Crook led a failed expedition in pursuit of Crazy Horse that was known as the Horsemeat March, and which ended in Deadwood, SD. Crook then ordered Colonel Ranald S. Mackenzie's 4th Cavalry into Wyoming. Mackenzie initiated the Dull Knife Fight, bringing about the end of Cheyenne resistance in the North Plains, which helped lead to the eventual surrender of Sitting Bull.

See also

• Red Cloud's War
• Black Hills War