Emperor Yūryaku
The tale of Urashima Tarō is developed from the brief mention in "Nihon Shoki" (Emperor Yūryaku Year 22) that a certain child of Urashima visited Horaisan and saw wonders. The later tale has plainly incorporated elements from the famous anecdote of "Luck of the Sea and Luck of the Mountains" (Hoderi and Hoori) found in "Nihon Shoki". The later developed Urashima tale contains the Rip Van Winkle motif, so some may consider it an early example of fictional time travel.