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History of Japan
Shōsōin
Periods Paleolithic 35,000–14,000 BC Jōmon 14,000–1000 BC Yayoi 1000 BC – 300 AD Kofun 300–538 AD Asuka 538–710 Nara 710–794 Heian Former Nine Years' War Later Three-Year War Genpei War 794–1185 Kamakura Jōkyū War Mongol invasions Genkō War Kenmu Restoration 1185–1333 Muromachi Nanboku-chō period Sengoku period 1336–1573 Azuchi–Momoyama Nanban trade Imjin War Battle of Sekigahara 1573–1603 Edo (Tokugawa) Tokugawa shogunate Invasion of Ryukyu Siege of Osaka Sakoku Perry Expedition Convention of Kanagawa Bakumatsu Meiji Restoration Boshin War 1603–1868 Meiji Ryūkyū Disposition Invasion of Taiwan (1874) Satsuma Rebellion First Sino-Japanese War Treaty of Shimonoseki Triple Intervention Invasion of Taiwan (1895) Colonization of Taiwan Boxer Rebellion Russo-Japanese War Treaty of Portsmouth Japan–Korea Treaty Colonization of Korea 1868–1912 Taishō World War I Intervention in Siberia Great Kantō earthquake 1912–1926 Shōwa Militarism Financial crisis Nanking incident Mukden Incident Invasion of Manchuria May 15 incident February 26 incident Anti-Comintern Pact Tripartite Pact Second Sino-Japanese War World War II Attack on Pearl Harbor Pacific War Atomic bombings Soviet–Japanese War Surrender of Japan Occupation of Japan Postwar Japan Anpo protests Economic miracle Asset price bubble 1926–1989 Heisei Lost Decades Great Hanshin earthquake Cool Japan Tōhoku earthquake Imperial transition 1989–2019 Reiwa COVID-19 pandemic Abe assassination Noto earthquake 2019–present
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Glossary History Timeline

Kōka (弘化) was a Japanese era name (年号, nengō, literally "year name") after Tenpō and before Kaei. This period spanned the years from December 1844 through February 1848.^[1] The reigning emperors were Ninkō-tennō (仁孝天皇) and Kōmei-tennō (孝明天皇).

• December 2, 1844 (Kōka gannen (弘化元年)): The new era name of Kōka, meaning "Becoming Wide or Vast", was created to mark a fire at Edo Castle in Tenpō 15.

The nengo was not changed concurrent with the accession of Emperor Komei; instead, the Kōka era was retained until about a year after the new emperor was enthroned.^[2]

• 1847 (Kōka 4): A major earthquake was recorded.
• 1848 (Kōka 5): The last subscription noh of the premodern era.^[3]

During these years, Hiroshige began making a series of prints showing beautiful women in contexts of famous places.^[4]

• Keene, Donald. (2005). Emperor of Japan: Meiji and his world, 1852-1912. New York: Columbia University Press. ISBN 9780231123419; OCLC 57750432
• Nussbaum, Louis Frédéric and Käthe Roth. (2005). Japan Encyclopedia. Cambridge: Harvard University Press. ISBN 978-0-674-01753-5; OCLC 48943301

• National Diet Library, "The Japanese Calendar" -- historical overview plus illustrative images from library's collection