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Sibley & Sully Expeditions of 1863 & 1864 - History Part 2: The Plan

The stated reason for Pope’s decision to mount a major military campaign into Dakota Territory was his perception of a real danger of further Indian attacks on the still-nervous frontier. There also may have been other military, economic, and political considerations. The fur trade had reached the Missouri River by 1792, and a succession of traders, explorers, scientists, and soldiers had been expounding the many values and assets of the upper Missouri region. Enough information had been gathered to suggest that fortunes could be made. By 1861 land companies were already offering potential town sites and farms for sale in parts of the region. Steamboats and wagon trains, filled with miners, merchants, and families headed toward the gold fields of Montana and Idaho, and it was known that a transcontinental railroad would be crossing these plains once the Civil War ended. Military control of the territory would aid all these possibilities.

Sibley Camp 1863

General Pope’s plan called for one army to march from Minnesota to the Devils Lake area, engaging the Sioux along the way, or pushing them westward towards the Missouri River. Meanwhile, a second army would advance northward along the Missouri, preventing escape across the river. Those caught between the two armies would either be captured or killed. The two armies were scheduled to rendezvous on July 25, 1863, at the Missouri River, where the field commanders could determine further action.

Alfred Sully
Alfred Sully

Sibley, who had displayed outstanding leadership as a colonel of volunteers during the conflict, was appointed to lead the Minnesota arm of the joint campaign. He was a veteran fur trader and knew the Dakota people well. As a former governor of Minnesota, General Sibley was well known and respected. General Alfred Sully, a West Point graduate experienced in Indian campaigns, was eventually chosen to command the second army.

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