Civil War fever is getting high, thanks to the 150th anniversary of the first year of the battle in 1861. Many collections of Civil War material will be put together in the next three years, as the world issues stamps commemorating the U.S. strife that pitted "brother against brother," as those aware of the personal toll that war took like to remind us.
One of the unusual aspects of that time, for stamp collectors and postal historians, was that there were two postal systems active -- the USPOD and the postal service of the Confederate States of America (CSA) Post Office Department. And no, this did not create a philatelic bounty for collectors of the day: they had far more serious matters on their minds. But it did create a historical record of the time in stamps and covers.
For today's collector, the items from that period of time are some of the most authentic and gritty bits of U.S. postal history that can be found. But if you are thinking of getting into Civil War topical collecting, you would do well to stay away from the great crush of new issues that is even now swamping collectors -- stamps issued by the USPS not included in the take-the-money-and-run list of issuers of dubious stamps -- and concentrate on pieces of the times. These include patriotic covers, mint and used CSA stamps, Sanitary Fair stamps and envelopes, so-called adversity covers (known made of wallpaper, or fashioned from an existing cover, turned inside out for a second use, when no stationery was available) and simple soldier mail, that can tell a story with infinitely more feeling than any textbook history of the War Between The States.
Just as first-hand accounts of the war are the most effective at presenting the true story of the conflict, actual artifacts, like letters home from battle sites or campgrounds, can be valuable collateral items to your topical collection, breathing life into the collection by linking it directly to the time commemorated on your stamps.
As for the South, those letters needed stamps for the envelopes that carried them. The fly in the ointment was that the Union had demonetized the stamps that were available before the war, printing new ones that were kept out of the hands of the Confederates. So the South did the only thing it could do under the circumstances: It printed its own stamps.
Of course, an argument could be made that this is not the time to buy Civil War material. You can't hate dealers for trying to get the most for their items while interest is high. Of course, you could wait a few years until prices cool down; but by that time maybe your interest would too.
All that being said, the United States Civil War is a great subject for a topical stamp collection. Few topics have greater historic resonance. There is enough material available, both old and new, that you will never run out of items to add to your collection.