Army of the Southwest, United States of America

December 25, 1861–December 13, 1862

The Army of the Southwest was a short-lived Union force organized on December 25, 1861, to resist Confederate forces operating in Missouri.

General Samuel Curtis Ryan, USA, Civil War

Samuel R. Curtis commanded the Army of the Frontier from December 25, 1861 – August 29, 1862 [Wikimedia Commons]


When the American Civil War began, the people of the border state of Missouri had highly divided sympathies. Although many Missourians favored remaining in the Union, Governor Claiborne Jackson was a strong proponent of secession. Despite his secessionist leanings, Jackson declared his support for the Union and affirmed Missouri’s neutrality by agreeing to terms of the Price-Harney Truce on May 12, 1861. When President Abraham Lincoln requested 75,000 troops from Missouri to take up arms against the Confederacy, Jackson withdrew his support of neutrality. A subsequent meeting between Jackson and Union Brigadier General Nathaniel Lyon did not resolve the matter. Instead, Lyon’s Army of the West and the Missouri State Guard, commanded by former Missouri Governor Sterling Price, engaged in a series of minor battles during the summer of 1861 for control of the state.

Confederate Presence in Missouri

By mid-July, Lyon’s army had driven Price’s forces into the southwestern corner of Missouri, where they received reinforcements from other southern states. Brigadier General Ben McCulloch commanded the newly formed combined Confederate force. Rather than stand by and watch McCulloch’s army continue to grow, Lyon determined to go on the offensive. On August 9, 1861, he led about 5,400 Union soldiers out of Springfield to assault over 11,000 Confederates encamped near Wilson’s Creek, approximately twelve miles southwest of the city.

Battle of Wilson’s Creek

Lyon surprised the Confederates with an attack on the morning of August 10 near Wilson’s Creek. During a hard day of fighting at the Battle of Wilson’s Creek, Confederates killed Lyon, and the Federals exhausted their ammunition, forcing them to abandon their offensive. The Confederates were too spent to pursue. Control of Missouri was still undecided.

Consolidation of Confederate Forces

After the Battle of Wilson’s Creek, discord between McCulloch and Price resulted in the former moving back into Arkansas, while the latter continued operations in Missouri. President Jefferson Davis intervened, seeking to settle the differences between McCulloch and Price and to coordinate operations west of the Mississippi by creating the Trans-Mississippi District. In January 1862, Davis appointed Major General Earl Van Dorn to command the new district. On January 29, Van Dorn assumed command, established his headquarters at Pocahontas, Arkansas, and began organizing his forces.

Army of the Southwest Origin

On the Union side, things were also in disarray after the Battle of Wilson’s Creek. Ineffectual leadership had plagued the Western District. Seeking more stability, in November 1861, the Lincoln administration appointed Major General Henry W. Halleck, known for his organizational skills, to command the district. On December 25, Halleck appointed Brigadier General Samuel R. Curtis to command the Southwestern District of Missouri (Special Orders, No. 92, Department of the Missouri). The troops under Curtis’ command became known as the Army of the Southwest.

Controversy and Reorganization

Halleck’s selection of Curtis was controversial because many of the residents and volunteers in the Western District were German Americans who preferred Brigadier General Franz Sigel who shared their ethnicity. Halleck, however, was skeptical of Sigel’s leadership abilities after the latter’s performance at Wilson’s Creek. When Sigel learned that Halleck had passed him over, he wrote to Curtis on December 26, 1861, threatening to resign.

Sigel’s complaints became a cause célèbre amongst German-Americans that eventually reached the national press, the halls of Congress, and President Lincoln’s office. After several weeks of backroom negotiations, Halleck and Curtis defused the matter by organizing the Army of the Southwest along ethnic lines. They gave Sigel overall command of the 1st and 2nd Divisions, commanded respectively by Colonel Peter J. Osterhaus and Brigadier General Alexander Asboth. Brigadier General Jefferson C. Davis commanded the 3rd Division, which comprised native-born Americans.

Into Arkansas

Eager for action after assuming command of the Army of the Southwest, Curtis struck out after Price in January 1862 and quickly drove him out of Missouri, into Arkansas. By February, Curtis crossed into Arkansas but had to halt his pursuit because his supply lines could not support further advancement. Not wanting to retreat, he established a base along Little Sugar Creek, just south of a hostelry named Elkhorn Tavern, and began foraging operations.

Battle of Pea Ridge

Meanwhile, Van Dorn developed ambitious plans to sweep through Missouri, capture St. Louis, and threaten Union operations in Kentucky. Van Dorn’s first order of business was to drive Curtis out of Arkansas. On March 4, Van Dorn started north from Fayetteville, Arkansas, with approximately 16,000 troops. His plan was to advance north as quickly as possible and to surprise Curtis’s scattered army before it had time to concentrate. After three days of forced marching through harsh winter weather, the Confederates approached Curtis’s position. The Confederate soldiers were cold, hungry, and exhausted, but Van Dorn pressed the advance.

Learning of Van Dorn’s advance, Curtis concentrated the 10,500 soldiers under his command and established a strong defensive position on Pea Ridge. The two armies engaged from March 6–8, 1862, with the Army of the Southwest emerging victorious at the Battle of Pea Ridge. The resounding Union victory secured Federal control of Missouri and it enabled the Union to focus on other areas in the Mississippi Valley. In the aftermath, Federal officials transferred Much of the army to Milliken’s Bend, Louisiana, March 13-26, and created the 14th Division of the 13th Army Corps (General Orders, No. 50, 13th Army Corps).

Threatening Little Rock

After the Battle of Pea Ridge, Curtis severed ties with his supply lines and pursued Van Dorn’s army farther into Arkansas, while living off of the land, much as Major General William T. Sherman would do in Georgia two years later. Curtis never caught up with Van Dorn, but he temporarily forced the Confederate state government to abandon Little Rock when his troops threatened the state capital in May 1862.

Battle of Cotton Plant

In July 1862, Curtis and the Army of the Southwest moved across northern Arkansas toward the Mississippi River port of Helena. On July 12, 1862, three regiments of Texas cavalry commanded by Colonel William H. Parsons tried to prevent three brigades of the Army of the Southwest from crossing the Cache River. Although outnumbered, the Federals, commanded by Colonel Charles E. Hovey, repulsed poorly organized Confederate attacks until reinforcements arrived. The Union victory at the Battle of Cotton Plant (aka the Battle of Hill’s Plantation) opened the door for the occupation of Helena on July 12, 1862.


For the next few months, the Army of the Southwest underwent a flurry of abbreviated command changes as the War Department siphoned off its troops to support the Vicksburg Campaign. On August 29, 1862, after Curtis took leave to travel to a railroad convention in Chicago, Brigadier General Frederick Steele assumed command of the army (General Orders, No. 42, Army of the Southwest). Steele served only briefly before being replaced by Eugene A. Carr on October 7, 1862, (General Orders, No. 50, Army of the Southwest). By this time army officials had transferred much of the Army of the Southwest to the Army of the Tennessee and the Army of the Mississippi. On November 14, 1862, the War Department ordered Brigadier General Willis A. Gorman “to report in person to Major General S. R. Curtis, commanding Department of the Missouri, at Saint Louis, Mo., for orders.” Curtis placed Gorman in charge of the Army of the Southwest and the troops in the District of Eastern Arkansas. On December 13, 1862, the War Department merged the two forces, ending the existence of the Army of the Southwest.

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  • Article Title Army of the Southwest, United States of America
  • Date December 25, 1861–December 13, 1862
  • Author
  • Keywords army of the southwest
  • Website Name American History Central
  • Access Date May 22, 2024
  • Publisher R.Squared Communications, LLC
  • Original Published Date
  • Date of Last Update January 12, 2024