The first diplomatic mission to the United States left Japan with a seventy-four person staff aboard the USS Powhatan. They arrived in Hawaii on March 5, 1860, left the islands on March 18, 1860 and arrived at the Mare Island Naval Base in San Francisco a little over a week later. They then traveled to Washington, D.C. via the Panama route. The embassy concluded its four month visit in June 1860. (By John Osborne)
Chitoshi Yanaga, "The First Japanese Embassy to the United States," in Ellis S. Krauss and Benjamin Nyblade (eds.), Japan and North America: First Contacts to the Pacific War (New York: Routledge, 2004), 40-41.