Camp Jackson Affair - Background

Background

January through April 1861 saw furious military organization in Missouri. Pro-secessionists established Minutemen para-military groups, usually with the overt support of state authorities. In February, the St. Louis-area Minutemen were enrolled by Brigadier General Daniel Frost as companies in a new Second Regiment of the Missouri Volunteer Militia. That same month, a new law banned militia activity outside the framework of the Missouri Volunteer Militia, forcing Unionist activists to organize in secret. In March, the Missouri Constitutional Convention of 1861 voted 98 to 1 to stay in the Union but not supply weapons or men to either side if war broke out.

On April 20, eight days after the start of the war at Fort Sumter, a pro-Confederate mob at Liberty, Missouri, seized the Liberty Arsenal and made off with about 1,000 rifles and muskets. This sparked fears that Confederates would also seize the much larger St. Louis Arsenal, which had nearly 40,000 rifles and muskets — the most of any slave state.

On April 23, on orders of the War Department, Union Captain Nathaniel Lyon temporarily replaced Brigadier General William S. Harney as (acting) Commander of the U.S. Army's Western Department. Lyon began enlisting and arming St. Louis Unionist volunteers, an action previously ordered by the Secretary of War, but not acted on by General Harney. Most of Lyon's early recruits were German immigrants and members of the Wide Awakes political organization. According to one estimate, 80% of the volunteers in the first Missouri Volunteer regiments were Germans. The Germans in particular were unpopular with many native-born Missourians with Southern backgrounds, who deeply resented their anti-slavery views. On the orders of the War Department, in the early morning hours of April 26, U.S. Regulars, Illinois state troops, and Missouri volunteers loaded 21,000 of the Arsenal's 39,000 weapons on the steamer City of Alton, which carried them across the river to Illinois.

In mid-April, Missouri Governor Claiborne Fox Jackson, who had been elected on the ticket of the (Unionist) Douglas faction of the Democratic party, but privately supported secession, had sent two pro-secessionist militia officers (Colton Green and Basil Wilson Duke) to Confederate President Jefferson Davis, with a letter asking for heavy artillery with which to attack the St. Louis Arsenal. Around May 1, Jackson called out the Missouri Volunteer Militia for "maneuvers". These took place about 4.5 miles northwest of the arsenal at an encampment christened "Camp Jackson" by the militiamen and located at Lindell's Grove (then outside the city of St. Louis, and today the site of the campus of St. Louis University on Lindell Boulevard). On May 9, the steamer 'J.C. Swon' delivered the Confederate aid: two 12-pound howitzers, two 32-pound siege guns, 500 muskets, and ammunition in crates marked as Tamoroa marble. The munitions had been captured by the Confederates when they seized the Federal arsenal at Baton Rouge. MVM officers met the shipment at the St. Louis riverfront, and transported it to Camp Jackson, six miles inland.