The Confederate States Army (CSA), was organized in
February 1861 to defend the newly formed Confederate States of America
from military action by the United States government during the American
Civil War. As many as 1.4 million men fought in the Army throughout the
war. Although it won a significant number of battles (particularly in
the Eastern Theater under General Robert E. Lee), a lack of centralized
control of the Army and the logistical and manpower advantages of the
United States doomed the CSA to eventual failure and the last of its
field armies surrendered in May 1865. The Confederate War Department was
established by the Confederate Congress in an act on February 21, 1861.
The Confederate States Army was actually three organizations:
1--The Army of the Confederate States of America (ACSA)was the regular army, organized by Act of Congress on March 6, 1861. It was authorized to include 15,015 men, including 744 officers, but this level was never achieved. The men serving as (full) generals, such as Samuel Cooper and Robert E. Lee, were enrolled in the ACSA to ensure that they outranked all militia officers.
2--The Provisional Army of the Confederate States (PACS) was authorized by act of Congress on February 28, 1861, and began organizing on April 27. Virtually all regular, volunteer, and conscripted men preferred to enter this organization since officers could achieve a higher rank in the Provisional Army than they could in the Regular Army. If the war had ended successfully for them, the Confederates intended that the PACS would be disbanded, leaving only the ACSA.
3--State Militias were organized and commanded by the state governments, similar to those authorized by the United States Militia Act of 1792. (Wikipedia, the free encyclopedia)
Civil War Military Action
Where it was, in rough order of states in which more and less action occurred
Virginia. The most, and the most important action by far, mainly between Richmond and Washington. Both sides wanted to protect their capitol city and capture the other's. Some battles: 1st/2nd Manassas/Bull Run (both CSA), Fredricksburg (CSA), Chancellorsville (CSA), Jackson's Valley Campaign (CSA), The Seven Days (CSA), The Wilderness (inconclusive), Spotsylvania (CSA), Cold Harbor (CSA), sieges of Richmond, Petersburg; Lee's surrender at Appomatox Courthouse.
Tennessee. Actions throughout the war. Forts Henry (USA) and Donelson (USA), Shiloh (USA), Memphis (USA), Stone River/Murfreesboro (USA), Chattanooga (USA), Missionary Ridge (USA), Franklin (USA), Nashville (USA), cavalry raids by N.B. Forrest (CSA).
Mississippi. Action throughout the war. Corinth (USA), the long Vicksburg campaign with several major battles (all USA), Sherman's march to Meridian (USA), Brice's Crossroads (CSA); various cavalry raids by N.B. Forrest (CSA).
Georgia (mainly 1864). Great Locomotive Chase ('62), Chickamauga (CSA), Sherman's crucial Atlanta campaign (USA) and march to the sea.
Alabama. Lots of minor action in N. Ala throughout the war, plus battles of Mobile Bay (USA) and Mobile (USA), cavalry raids by N.B. Forrest (CSA).
West Virginia. Minor battles in 1861. "Seceded" from Virginia and accepted into the union 1863. Several significant actions at Harper's Ferry.
Louisiana. Minor and mid-level action through most of the war. New Orleans (USA), Ft. Hudson (USA), Baton Rouge (USA), Red River Campaign (CSA).
Arkansas. Minor and mid-level action throughout the war.
Kentucky. Continual minor action until late in the war. Battles of Mill Springs (USA), Richmond (CSA), Perryville (USA); cavalry raids by J. H. Morgan (CSA).
South Carolina. Federal control and blockade of most coastal areas early in the war. No inland action until Sherman's highly destructive march across the state, spring of 1865.
North Carolina. Federal control and blockade of most coastal areas early in the war. No inland action until spring 1865 when Sherman arrived from S.C. and did some relatively minor damage. Johnston's surrender to Sherman.
Texas. A few minor or mid-level actions along the Gulf Coast, Brownsville to Galveston.
Missouri. A few minor engagements throughout the war.
Florida. One minor unsuccessful Union attempt to invade N. Florida.
Pennsylvania. Nothing significant . . . except Gettysburg!
Maryland. A smallish Confederate force went through western Md, briefly reached the outskirts of Washington, 1864. And the battle of Antietam/Sharpsburg (USA), the bloodiest single day of the war.
Ohio. One brief, unsuccessful Confederate raid by J. H. Morgan's cavalry raiders.
New Mexico Territory. One early attempt by a Confederate force from Texas to go across the Southwest and invade California. It was sent straggling back to Texas by Union garrisons in far western forts.
The Cost in Lives
About 620,000 Americans died in the war, roughly half on the battlefield, and half due to disease, accidents, and the like. This is approximately equal to Americans killed in all other wars combined from the Revolutionary War through the 1991 Persian Gulf War.
The ten costliest battles (killed, wounded, missing, captured):
1) Gettysburg PA, July 1-3 1863: 51,000 of 157,000. Winner: Union
2) Chickamauga GA, Sept 19-20 1863: 35,000 of 124,000. Winner: Confederacy
3) Chancellorsville VA, May 1-4 1863: 30,000 of 194,000. Winner: Confederacy.
4) Spotsylvania VA, May 8-19 1864: 27,000 of 133,000. Winner: Confederacy
5) Antietam/Sharpsburg MD, Sep 17, 1862: 26,000 of 127,000. Winner: Union.
6) The Wilderness VA, May 5-7 1864: 25,000 of 162,000. Inconclusive.
7) 2nd Manassas/2nd Bull Run VA, Aug 29-30 1862: 25,000 of 124,000. Winner: Confederacy.
8) Stone River/Murfreesboro TN, Dec 31 1862: 25,000 of 77,000. Winner: Union.
9) Pittsburgh Landing/Shiloh TN, Apr 6-7 1862: 24,000 of 103,000. Winner: Union.
10) Fort Donelson TN, Feb 13-16 1862: 19,000 of 48,000. Winner: Union.
USA and CSA armies were both organized in basically the same way
Company: at full strength, about 100 men commanded by a captain.
Battery: an artillery company that (at full strength) handled four cannons. Each cannon, when traveling, was attached to a two-wheel wagon (a limber) that carried ammunition. Six horses pulled a cannon plus limber. A four-wheel wagon (a caisson) carried more ammunition for each cannon, and six horses pulled each caisson. So, twelve horses per cannon! But on the road, horses pulling loads get tired, so there were twelve spare horses per cannon. Thus a full-strength battery company included about 100 men and 96 horses. Since both sides depended on volunteers for most of the war, often companies and regiments never attained "full strength," and as the war progressed many of them were reduced to much less than full strength.
Regiment: Two or more companies, commanded by a colonel. A full-strength regiment was somewhere around 1000 men. Sometimes, especially in the south, regimental colonels were elected by the troops.
Brigade: Two or more regiments, commanded by a brigadier (brigade) general. Brigadier generals varied enormously in ability and experience. Sometimes they were political appointees with zero military experience! When enough volunteers were recruited in a state, somebody had to be put in charge even if no one was available who was qualified. So local politicians who wanted a war record to further their political careers were sometimes appointed as brigadier generals after some lobbying with officials in Washington or Richmond. Of course experienced "regular army" brigadier generals held such appointees in low esteem. A few of them turned out to be very capable military leaders; a few of them had had prior military service; but most of them didn't.
Division: Two or more brigades, commanded by a major general.
Corps: Two or more divisions, sometimes commanded in CSA by a lieutenant general. In USA, by a senior major general.
Army: Two or more corps, commanded by a "commanding general" appointed by the commander in chief (Lincoln or Jeff Davis).
The USA had no lieutenant generals until Lincoln put Grant in charge of all Union armies, early 1864. It took a special act of Congress to make Grant a lieutenant general, because previously only one person had ever held that rank - George Washington. Both CSA and USA had several hundred generals. Many of them did not command any troops, but served in various headquarters staff positions. Which of several generals of the same rank was in command when several brigades or divisions fought together depended on seniority. The general who had gotten his promotion first was the commander, even though he may not have had as much experience as some others. Sometimes this led to jealousy and bitter complaints among generals. Of course the commander in chief (Lincoln, or Jeff Davis) could and sometimes did overrule the seniority system.