Antietam

which they operated or originated. Again, the North and South differed on how to name their armies and followed the general procedures they used to name battles. The Federals designated their armies for rivers while the Confederate armies took their names from the region of their assignment. Thus, the Union Army of the Potomac opposed the Confederate Army of Northern Virginia. This becomes even more confusing when the Union organization was the Army of the Tennessee as opposed to the Confederate-named Army of Tennessee.

Officer Ranks: Officers of both sides often had two ranks-one awarded by their state militia and another by the regular army. Even more confusion arises from the practice of both sides to award "brevet" promotions. These ranks, awarded for gallantry or meritorious action, were strictly honorary and had none of the authority or pay of the actual rank. Regular ranks are the ones most used in this work. Both armies followed the traditional ranks of lieutenant, captain, major, lieutenant colonel, colonel, and general. The two sides differed, however, in the rankings of their general officers. The Union maintained three ranks-brigadier general, major general, and lieutenant general, with only the most senior officer achieving this last rank. The Confederacy promoted officers to brigadier general, major general, lieutenant general, and general. Several officers achieved the designation of general with their seniority based on the date of their promotion.
Excerpted from The Civil War 100: The Stories Behind the Most Influential Battles, People and Events in the War Between the States by Michael Lanning All rights reserved by the original copyright owners. Excerpts are provided for display purposes only and may not be reproduced, reprinted or distributed without the written permission of the publisher.