- Confederate defeat: The Union Army, led by General George Meade, defeated the Confederate forces under General Robert E. Lee in Gettysburg, Pennsylvania, from July 1-3, 1863. The battle effectively ended Lee's second invasion of the North and halted the Confederate army's momentum to gain control of the war's eastern theatre.
- High casualties: Gettysburg saw some of the heaviest fighting and highest casualties of the war. With an estimated 51,000 total casualties (killed, wounded, and missing) from both sides, it became the deadliest battle ever fought in North America to date. The tremendous losses inflicted severe damage on the Confederate Army, weakening it significantly.
- Declining morale: The Confederate loss at Gettysburg was a major blow to the morale of its soldiers. The realization that the Union Army could decisively defeat them shattered the myth of Confederate invincibility and led to a decline in enthusiasm among Southern troops.
- Political impact: The victory at Gettysburg boosted Northern morale and strengthened President Abraham Lincoln's position and his policies for the war effort. It played a significant role in rallying public support for the Union cause and gave the President added credibility in pursuing the war to its end.
- Foreign perception: The Union victory at Gettysburg had international ramifications. It changed European perception of the war, increasing support for the Union and diminishing the chances of foreign intervention in favour of the Confederacy.
- Technological advancements: The American Civil war and particularly The Battle of Gettysburg, witnessed notable technological advancements. Union forces had access to more modern weapons and technology than the Confederates, including the use of improved artillery and more powerful rifles, which gave them an advantage in the engagements.