1861 Civil War Confederate Use of United States Postage

This cover tells a strange story

In December 1860 South Carolina became the first state to secede.  On April 12th the Confederates attacked Fort Sumter at Charlestown, S.C.  And even after that famous battle, the U.S. Post Office still delivered mail in Confederate states.  On June 1st the Confederate Post Office “took over” Southern postal routes.  This cover was mailed during that strange time after secession.