People will often cite to the Battle of New Orleans as a similar post-war battle, but in that case I believe they are mistaken as the Treaty of Ghent made explicit provision for the time-delayed cessation of hostilities, anticipating delays in notification.
Anyway, since the Confederate “states” were never truly independent and all their forces surrendered piecemeal in the field, it’s harder to pinpoint such a precise “end” to the war.
100% they knew.
After the war a lot of Confederate soldiers just became lawless wild west bandits and robbers. This is just what happens when you are a soldier, you lose, and your command breaks down. You become an outlaw without a banner (raiding merchant vessels is just what they were doing in the war too)
Here’s the timeline from the Wikipedia article, which looks like they found out about part of it in late June, but weren’t sure that the war was over until sometime in August.
On June 27, 1865, Waddell learned from a prize, Susan & Abigail, that General Robert E. Lee had surrendered the Army of Northern Virginia almost three months earlier at Appomattox Court House. *Susan & Abigail’*s captain produced a San Francisco newspaper reporting the flight from Richmond of the Confederate government 10 weeks previously. However, the newspaper also contained President Davis’ proclamation that the “war would be carried on with renewed vigor.”[8] Waddell then captured 10 more whalers in the space of seven hours just below the Arctic Circle.
On August 3, 1865, Waddell learned of the war’s definite end when Shenandoah encountered the Liverpool barque Barracouta, which was bound for San Francisco. Waddell was heading to the city to attack it, believing it weakly defended.[9] He learned of the surrender of Johnston’s army on April 26, and Kirby Smith’s army on May 26, and most crucially of the capture of President Davis. Captain Waddell then knew the war was over.[8]
Check out Sea of Grey, Tom Chaffin.
Sea of Gray: The Around-the-World Odyssey of the Confederate Raider Shenandoah by Tom Chaffin | Goodreads
IIRC, they got reports from American ship’s they considered unreliable, in context, but when they got independent confirmation, they ceased hostilities.
OTOH, the sailed from Alaska to England to avoid surrendering to a Union port out of fear of being summarily hanged as pirates, so when did they really believe it was over?
They’re still fighting it, some of them.
Tell me about it. You know, as a right of passage, the southern military school I attended had us new cadets reenact the charge some (draft dodging, treason-loving) cadets made against the (righteous) Union Army?
VMI? New Market?
‘fraid so.
VMI only recently stopped the practice of requiring first year students to salute a statue of Stonewall Jackson and didn’t stop until a Post article about racism on campus.
The Washington Post story outlines numerous student and alumni allegations mentioned in the state leaders’ letter, as well as a 2017 incident in which White cadets dressed up in boxes, representing the southern border wall, bearing a slur against Mexicans.
“I wake up every day wondering, ‘Why am I still here?’” a 20-year-old Black senior, William Bunton, told the newspaper.