Sterling Price in the context of "Western Theater of the American Civil War"

David Rice Atchison (August 11, 1807 – January 26, 1886) was a mid-19th-century Democratic United States Senator from Missouri. He served as president pro tempore of the United States Senate for six years. Atchison served as a major general in the Missouri State Militia in 1838 during Missouri's Mormon War and as a Confederate brigadier general during the American Civil War under Major General Sterling Price in the Missouri Home Guard. Some of Atchison's associates claimed that for 24 hours—Sunday, March 4, 1849, through noon on Monday—he may have been acting president of the United States. This belief, however, is dismissed by most scholars.

Atchison, owner of many slaves and a plantation, was a prominent pro-slavery activist and border ruffian leader, deeply involved with violence against abolitionists and other free-staters during the "Bleeding Kansas" events that preceded admission of the state to the Union.

Wilson's Creek National Battlefield, located near Republic, Missouri, preserves the site of the Battle of Wilson's Creek. Fought on August 10, 1861, the battle was the first major American Civil War engagement west of the Mississippi River. In the battle, a Confederate army commanded by Benjamin McCulloch and Sterling Price defeated a smaller Union army commanded by Nathaniel Lyon. However, the Confederates were unable to hold much of Missouri, and a Confederate defeat at the Battle of Pea Ridge effectively solidified Union control of the state. Major features include a five-mile automobile tour loop, the restored 1852 Ray House, and "Bloody Hill", the site of the final stage of the battle. The site is located near Republic in southwestern Missouri just southwest of the city of Springfield. It has been a unit of the National Park Service since 1960, and was listed on the National Register of Historic Places in 1966.

At the outbreak of the American Civil War in April 1861, Kansas was the newest U.S. state, admitted just months earlier in January. The state had formally rejected slavery by popular vote and vowed to fight on the side of the Union, though ideological divisions with neighboring Missouri, a slave state, had led to violent conflict in previous years and persisted for the duration of the war.

While Kansas was a rural frontier state, distant from the major theaters of war, and its Unionist government was never seriously threatened by Confederate military forces, several engagements did occur within its borders, as well as countless raids and skirmishes between local irregulars, including the Lawrence Massacre by pro-Confederate guerrillas under William Quantrill in August 1863. Later the state witnessed the defeat of Confederate General Sterling Price by Union General Alfred Pleasonton at the Battle of Mine Creek, the second-largest cavalry action of the war. Additionally, some of the Union's first Black regiments would form in the state of Kansas. These contributions would inform the complicated race relations in the state during the reconstruction era (1865–1877).

Alfred Pleasonton (June 7, 1824 – February 17, 1897) was a United States Army officer and major general of volunteers in the Union cavalry during the American Civil War. He commanded the Cavalry Corps of the Army of the Potomac during the Gettysburg campaign, including the largest predominantly cavalry battle of the war, Brandy Station. In 1864, he was transferred to the Trans-Mississippi theater, where he defeated Confederate General Sterling Price in two key battles, including the Battle of Mine Creek, the second largest cavalry battle of the war, effectively ending the war in Missouri. He was the son of Stephen Pleasonton and the younger brother of Augustus Pleasonton.