[ The Dakota War: The United States Army Versus the Sioux, 1862-1865 by Micheal Clodfelter (McFarland, 1998) Hardback*, Library binding, illustrations, maps, photos, notes, appendices, pp. 247.]
Although the story of the 1862 Santee uprising is told well in both Duane Schultz's Over the Earth I Come: The Great Sioux Uprising of 1862 and the Minnesota Historical Society's publication of Kenneth Carley's The Sioux Uprising of 1862[I haven't read the more recent works by Jerry Keenan and Hank Cox], the continuation of the war westward into the Dakota territory from 1863-1865 is largely ignored in the literature. Thankfully, Micheal Clodfelter has provided us with a first-rate overview history of the Sibley-Sully campaigns with his book The Dakota War: The United States Army Versus the Sioux, 1862-1865.
While most studies end with the mass hanging at Mankato, Clodfelter details the several campaigns that served to drive the hostiles out of Minnesota and into Canada and the Dakota plains. In 1863, General John Pope directed a two-pronged campaign against the Sioux (most of the individuals that participated in the worst atrocities of the 1862 uprising remained at large). One wing under Henry Hastings Sibley followed the Minnesota River toward the Devil's Lake region in the Dakota territory, fighting successful but indecisive battles at Big Mound, Dead Buffalo Lake, and Stony Lake. Instead of destroying the Sioux, the fighting pushed them over the Missouri River to safety. The other wing, commanded by Alfred Sully, was late in its scheduled rendezvous with Sibley but caught the Sioux after they recrossed the Missouri in the wake of Sibley's withdrawal. Sully's larger victory at Whitestone Hill concluded the year's campaigning, leaving the Sioux chastisted but far from defeated.
Sully's 1864 campaign utilized more mounted forces and his command was able to catch the Sioux and inflict fairly significant losses upon them at the Battle of Killdeer Mountain. His column then continued on westward into the Badlands before returning to Minnesota. The goal of establishing a fort on the Yellowstone River was unmet. The next year's campaigning accomplished little, and with the end of the Civil War the plains wars really had only begun.
Clodfelter's account of these conflicts demonstrates the difficulty of utilizing large, ponderous army columns (and their slow supply trains) in order to catch concentrations of fleet Indians. The lack of a preexisting network of forts in the territory further hampered efforts to bring the hostile groups to heel; the Indians could always just disperse when confronted by white columns coming from a single direction. Although casualties in these battles were comparatively low by Civil War standards, Sioux losses at Whitestone Hill and Killdeer Mountain were nevertheless significant. In battle, the decisive factor was often the U.S. army's artillery. Certainly, the Sioux had nothing to match it and the psychological effect of exploding shells was crushing. Furthermore, compared with the conflicts of the next decade, the Indians' poor arms (mainly bows and arrows) left them ill equipped to handle any sizeable concentration of bluecoats, who were armed with modern shoulder arms.
The Dakota War packs an impressive amount of information into a study of relatively short length. Unlike most Indian Wars histories, the maps provided are detailed and plentiful, allowing the reader to easily trace the movements of the army columns as they travelled hundreds of miles over the parched plains. Although rather primitively drawn, the tactical battle maps are exceptional in their level of detail.
Well researched, and employing good writing and deft analysis, The Dakota War is noteworthy military history. This book is by far the best work written on the subject and is highly recommended.
* - I believe the hardcover referenced above is out of print, but the publisher has released a paperback edition.