This week is the 200th anniversary of Lord Byron’s death. The most famous poet of his age (an odd phrase now) died fighting for Greek independence in the marshes of Missolonghi. “Who would write, who had anything better to do?” he once said. There was a strange contest over his body and memory: The lungs and larynx remained in Greece but friends carried the rest back to England, where huge crowds followed the funeral procession. A month after his death, his former editor burned his memoirs, worried they would damage the reputation of a superstar read around the world. Does...