John Wilkes Booth and his friend Davy Herold stood on the Executive Mansion lawn on the evening of April 11, 1865, listening to President Lincoln speak from a second-story window.

It was the first time President Lincoln publicly called for the vote for African-Americans.

Booth became enraged. “That means nigger citizenship,” he said. “That is the last speech he will ever make.”

Dr. Charles Leale, the young army surgeon who would try to save the president after Booth shot him, was also standing on the lawn. Leale hadn’t intended to come to the speech. Out for a walk after work, he was swept up into the crowd walking down Pennsylvania Avenue.