The 1950’s trial and execution of Ethel and Julius Rosen­berg—the only Americans executed for espionage-related activity during the cold war—still capture the attention of scholars and artists. A new website from The Howard Gottlieb Archival Research Center at Boston University makes available over 500 letters from and about the Ro­­senbergs, including legal material, correspondence between the couple and Ethel’s final, hastily penned note to her children.