HistoryData
war1865

Battle fought in Wyoming in 1865

July 26, 1865

The Battle of Platte Bridge was the culmination of a major 1865 Lakota Sioux and Cheyenne offensive against U.S. Army positions in Wyoming.

Quick Facts

Year
1865
Category
war

Key Facts

Date
July 26, 1865
Estimated warrior force
3,000 warriors
U.S. defenders at bridge
120 soldiers
U.S. soldiers killed
29 soldiers
Indian casualties (minimum)
8 dead
Wagon train guard size
28 soldiers

By the Numbers

261,865
Date
3,000warriors
Estimated warrior force
120soldiers
U.S. defenders at bridge
29soldiers
U.S. soldiers killed

Location

Map of Casper, United StatesMap of Casper, United StatesCasper, United States

Cause → Event → Consequence

Cause

Beginning in May and June 1865, Lakota Sioux and Cheyenne warriors launched raids on U.S. Army outposts and stagecoach stations across a wide area of Wyoming and Montana. By July, the tribes had assembled a large combined force estimated at 3,000 warriors and directed their offensive toward the strategically important Platte Bridge crossing.

Event

On July 26, 1865, a force estimated at 3,000 Lakota Sioux and Cheyenne warriors attacked the Platte Bridge station on the North Platte River, guarded by only 120 U.S. soldiers. Fighting occurred near the bridge and separately against a 28-man wagon train escort several miles away. The Indians killed 29 soldiers while suffering at least eight dead themselves.

Consequence

The battle represented the high point of the summer 1865 Indian offensive against U.S. military infrastructure in the region. The U.S. Army suffered significant casualties relative to its small garrison forces, highlighting the vulnerability of its outposts along key travel and communication routes through Wyoming and Montana during this period of intensified conflict.

Belligerents & Mobilization Analysis

Side A

1 belligerent

United States Army
Peak Mobilized Forces148
Estimated Casualties29
Casualty Rate19.6%
Forces vs Casualties ratio
0CasualtiesMobilized

Side B

1 belligerent

Lakota Sioux and Cheyenne
Peak Mobilized Forces~3K
Estimated Casualties8
Casualty Rate0.3%
Forces vs Casualties ratio
0CasualtiesMobilized
Total Casualties (all sides)
37
Outcome
Indian tactical victory; 29 U.S. soldiers killed against at least 8 Indian dead

Timeline Context

Timeline around 186518651862186318641866186718681865 siege during the American Civil War1865 meetings between the US govt and Indian tribes1865 Colorado War battleBattle of Bone Pile CreekWorld's fair in Porto, PortugalSeries of military operations during the American Civil War1865–1870, United States v. Natives1865 American Civil War battlebattle-of-platte-bridge-1865