EXTREMELY FINE. A SUPERB EXAMPLE OF THE "SOUTHN. LETTER UNPAID" MARKING USED TO CANCEL THE UNITED STATES STAMP.
The U.S. May 27 suspension order prohibited post offices from forwarding southbound mail to disloyal Southern states. However, northbound mail continued to be sent via Louisville. Through June 6, northbound mails were forwarded to Louisville from Memphis or Nashville. From June 7 through 12, only the Nashville post office forwarded mail to Louisville, and Louisville continued to forward mail north. With the resignation of W. D. McNish as Nashville's Federal postmaster on June 12 and the withdrawal of the U.S. mail agent from this route, Louisville held the mails still being sent north by the discontinued post office at Nashville. On June 24, Dr. John J. Speed, the postmaster at Louisville, was advised to forward letters from the South to the loyal states after removing postage. With approximately 5,000 such letters accumulating at Louisville by this date, Postmaster Speed employed a more practical means of invalidating postage by creating the "Southn. Letter Unpaid" handstamp. Louisville started marking letters on June 25, but this first group did not have a datestamp. The subsequent group and all of those thereafter have the Louisville circular datestamp (June 27, 28 and 29 being the most common dates). As a matter of record, this is the only recorded "Southn. Letter Unpaid" cover with the June 30 datestamp.
United States postage stamps and stamped envelopes used from the South were regarded as contraband and were refused as prepayment. There are 29 "Southn. Letter Unpaid" covers recorded in the Special Routes book (No. 25 has been deleted as a fake since publication), of which only 13 have the 3c U.S. adhesive stamp used to pay the domestic rate. Two of the 13 are used with the New Orleans provisional (offered in this sale) and one is in the Smithsonian National Postal Museum, leaving only ten 3c 1857 Issue stamped covers with the "Southn. Letter Unpaid" marking. This cover has a very early origin date -- May 31 -- and since it was mailed while the post office in Milford, Texas, was still technically as U.S. post office, there was no Confederate postage paid. Only two "Southn. Letter Unpaid" covers with only U.S. postage are recorded, both dated May 31 from Texas (the other is in the Smithsonian National Postal Museum collection).
Special Routes Census No. SLU-17. Ex Caspary and Kilbourne.