In the July 1863 battle, considered the turning point of the war, federal forces fought back a Confederate invasion of Pennsylvania. Lincoln's speech was delivered more than four months later, at the dedication of a national cemetery to bury the battle's casualties.
In the short oration, he spoke of how democracy itself rested upon "the proposition that all men are created equal," a profound and politically risky statement for the time. Slavery and the doctrine of states' rights would not hold in the "more perfect union" of Lincoln's vision.
"In 272 words he put together what everyone was thinking, what everyone should know," said park historian John Heiser. Because of varying transcriptions, scholars generally put the text at 268 to 272 words.
Supreme Court Justice Antonin Scalia administered the oath of allegiance to a group of 16 immigrants, telling them the national identity is unique, illustrated by the existence of the word "un-American" and by the people's "fidelity to certain political principles."
Greta Myer, 44, decided to make the six-hour trip from Akron, Ohio, with her husband and son after spending a week in Gettysburg earlier in the year.