The Declaration of Independence is the birth certificate of the American nation—the first public document ever to use the name "the United States of America"—and has been fundamental to American history longer than any other text. It enshrined what came to be seen as the most succinct and memorable statement of the ideals on which the U.S. was founded: the rights to life, liberty and the pursuit of happiness; the consent of the governed; and resistance to tyranny.

But the Declaration's influence wasn't limited to...