State Adjutant General Reports, typically written by a State Adjutant General to his Governor, can be a rich source for information on the role of individual Union states in the American Civil War. The State Adjutant General is the senior military officer and de facto commander of all of that state’s National Guard and militia forces. They typically are appointed by and subordinate only to the Governor.
Adjutant General reports can include the offfice's correspondence with the Governor, the U.S. War Department (many involve Edwin M. Stanton, the U.S. Secretary of War from 1862-68, or Simon Cameron, the Secretary of War from 1860-61), and the U.S. Adjutant General.* Much of this correspondence concerns the federal government's call to state governments to raise and equip volunteer troops and send them to the aid of the Union Army. Also included are requests for calling out of state militia to help quell resistance from elements in their home state.
Some states' reports record the names of all active state guardsmen and militia, their rank, the arm of the military that they belong to (infantry, artillery, cavalry, etc.), and where they were from in their state. The Missouri reports do not list names of all men, but do show officer names for each company. Adjutant General reports from years following the war can tell of the individual outcomes of each soldier (whether he died, or when discharged).
Missouri Adjutant General reports contain many of the same elements as those for other states: general correspondence, supply listings, troop registries, etc. The Missouri reports also had, in addition to those other items, short histories of the various Missouri regiments. These accounts, called “Historical Memoranda,” cover the regiment’s entire activity during the period when it was active. The Memoranda tells where that regiment was assigned, lists battles or skirmishes it may have fought in, and indicates how many casualties and deaths were suffered within the unit. These mini-histories provide a more personal look into the rigors of military duty during the Civil War and offer detailed descriptions of the movements of a particular body of troops.
Most of MU Libraries' state Adjutant General reports are housed in Special Collections and are findable through the MERLIN catalog. Try this link to see a sample, or for best results, do a keyword field search on "Adjutant General" and [state].
*See MOBIUS record for Letters Received by the Office of The Adjutant General (Main Series),1861-1870 [microform].