General Robert E. Lee [CS] advances into Pennsylvania where he meets George Meade [US]. First battling north of the city, by the second day Union forces had retreated south, forming a strong line as men arrived almost continuously. On the third day, the infamous Pickett's Charge marked the end of the Confederates hope for a victory
John Pemberton, commander of Confederate forces at Vicksburg asks Ulysses S. Grant for terms. Grant demands an unconditional surrender. Pemberton refuses. Late in the evening, Grant offers excellent terms and Pemberton accepts.
Rear Admiral Samuel Du Pont, South Atlantic Blockading Squadron, is relieved of duty over the lack of ability of the Navy to make headway against the fortifications of Charleston, according to Secretary of the Navy Gideon Welles. He is replaced by John Dahlgren.
The 54th Massachusetts, comprised primarily of free blacks from Massachusetts and Pennsylvania, attack Battery Wagner in Charleston Harbor, losing 30% of their men and forcing Quincey Gillmore to lay siege to the city. The film "Glory" is based on this action.
While crossing the Ohio River into Kentucky at Buffington Island, John Hunt Morgan's raiders stumble onto a fortified position. Federals manage to kill or wound 120 and capture 700 men and most of the rest return to Ohio to find an alternate crossing.