From the WHS Web Site:
The Society’s online collection about Wisconsin in the Civil War recently added more than 350 Civil War maps. They join 20,000 pages of letters, diaries, memoirs and photographs already available.
About 50 of the maps published while the fighting was underway informed citizens on the homefront about the war’s progress. For example, a War Telegram Marking Map published in Boston in 1862 shows rivers, roads and railroads in Virginia and Maryland during the Peninsula and Maryland campaigns of that year.
The rarest map in the collection is a Confederate map issued in Augusta, Georgia, in 1861. This Map of the Seat of the War used an unusual photograph-based method and shows portraits of seven Confederate leaders in its margins. Only a handful of copies survived the war.
Most of the maps in the collection were produced after the war to illustrate specific battles. Users who are reading diaries or letters can use them to follow troop movements and locate opposing forces. The most important battles, such as Antietam or Gettysburg, are represented by multiple maps showing troop positions at several times through the engagement. Most originally appeared in Matthew Forney Steele’s American Campaigns (Washington, D.C.: War Dept., 1909), a textbok used in U.S. military academies.