Button Gwinnett was a relatively obscure member of the Continental Congress when he signed the Declaration of Independence in August 1776. Nine months later he was killed in a duel.

That makes his signature one of the most valuable in the world, comparable to those of Julius Caesar and William Shakespeare. Only 51 examples exist. This January it was discovered that he’d signed a Wolverhampton marriage register in 1757, five years before departing England for America. That autograph was valued at £500,000.