 The Tairō Ii Naosuke had been assassinated on March 24; and accounts of the event were sped by pony express across the American continent.This murdered official had been the highest ranking signer of the Japanese-American 1858 "Harris Treaty", which was a follow-up to the 1854 Treaty of Kanagawa.The delegation continued on to New York City, where their procession up Broadway from the Battery was a grand parade.