Emperor Kaika (開化天皇)
Emperor Kaika (208 B.C. – May 21, 98 B.C.) is the ninth emperor (reigned from November 12, 158 B.C. to May 21, 98 B.C.) written in "Kojiki" (The Records of Ancient Matters) and "Nihonshoki" (Chronicles of Japan). He is also called Wakayamatonekohiko obibino mikoto or Wakayamatonekohiko obibino mikoto (in Kojiki).
The title 'Yamatoneko' is used for the seventh Emperor Korei, the eighth Emperor Kogen, the ninth Emperor Kaika, and after an interval, the twenty-second Emperor Seinei (Kojiki), and is also found in the titles of such emperors as Jito, Monmu, Genmei, and Gensho (Nihonshoki and "Shoku Nihongi" [Chronicle of Japan Continued]), who existed in the period from the late seventh through the early eighth century when the compilation of the Kojiki and Nihonshoki was in the final stage. Therefore, it is suspected that the titles for the seventh, eighth and ninth emperors were made with reference to the titles of the existent emperors in the later period when the compilation of the Kojiki and Nihonshoki was in the final stage.
He is one of so-called Kesshi-Hachidai (Eight Undocumented Sovereigns), but some believe that he actually existed.
His palace was Kasugano izakawanomiya (located at Musanimasu-jinja Shrine in Mise Town, Kashihara City, Nara Prefecture according to legend). It is also referred to as 'Kasuganoizakawanomiya' in Kojiki.
No specific records exist even for the period before the enthronement of the Emperor Sujin whose deeds were abundantly recorded. He was formally installed as Crown Prince in January, 193 B.C., and was enthroned in November, 158 B.C. He passed away after 60 years of reign. He was then at age 63 according to Kojiki or 115 (or 111?) according to Nihonshoki.
He was buried in Kasuganoizakawa no sakanoeno misasagi. It is referred to as 'Zakawanosakanoe' in Kojiki. The mausoleum is identified as Nenbutsujiyama-kofun Tumulus (about 100-meter-long keyhole-shaped burial mound) in Aburasaka Town, Nara City, Nara Prefecture.