Reading a book called The Civil War Day by Day, by E.B. Long. It's exactly what you would think--a day by day chronicle of the major events of the war. First-rate reference book.
March 7, 1863, Saturday. Among other things, "In Baltimore the Federal army forbade the sale of 'secession music' and confiscated all such song sheets."
Didn't see any thread here relating to secession music of the period (1861-1865), so I thought I'd mention it.
From Wikipedia: Music of the American Civil War.
"The Bonnie Blue Flag" would have been a secession song. "Dixie."