Jōgen (Kamakura period)
Jōgen (承元) was a Japanese era name (年号, nengō, lit. year name) after Ken'ei and before Kenryaku. This period spanned the years from October 1207 through March 1211. The reigning emperors were Tsuchimikado-tennō (土御門天皇) and Juntoku-tennō (順徳天皇).
Jōgen (承元) was a Japanese era name (年号, nengō, lit. year name) after Ken'ei and before Kenryaku.  This period spanned the years from October 1207 through March 1211. The reigning emperors were Tsuchimikado-tennō (土御門天皇) and Juntoku-tennō (順徳天皇).

Change of era
1207 Jōgen gannen (承元元年); 1207: The new era name was created to mark an event or a number of events. The previous era ended and a new one commenced in Ken'ei 2, on the 25th day of the 10th month of 1207.

Events of the Jōgen era
1208 (Jōgen 2, 6th month): The emperor went to the Kumano Sanzan Shrine.
1210 (Jōgen 4, 5th month): The emperor returned to the Kumano Shrine.
1210 (Jōgen 4, 6th month): The emperor accepted Hideyasu, prince of Kazusa, as part of the court.
1210 (Jōgen 4, 8th month): The emperor visited the Kasuga Shrine.
1210 (Jōgen 4, 9th month): A comet with a very long tail appeared in the night sky.
1210 (Jōgen 4, 25th day of the 11th month): In the 12th year of Tsuchimikado-tennō's reign (土御門天皇12年), the emperor abdicated for no particular reason; and the succession (senso) was received by his younger brother, the second son of the former-Emperor Go-Toba. Shortly thereafter, Emperor Juntoku is said to have acceded to the throne (sokui).

Notes
References
Brown, Delmer and Ichiro Ishida. (1979). The Future and the Past: a translation and study of the 'Gukanshō', an interpretative history of Japan written in 1219.  Berkeley: University of California Press. ISBN 978-0-520-03460-0; OCLC 5145872
Kitagawa, Hiroshi and Bruce T. Tsuchida, eds. (1975). The Tale of the Heike. Tokyo: University of Tokyo Press. 	ISBN 9784130870245; ISBN 9784130870238; ISBN 9780860081883; ISBN 9780860081890; OCLC 193064639
Nussbaum, Louis-Frédéric and Käthe Roth. (2005). Japan encyclopedia. Cambridge: Harvard University Press. ISBN 978-0-674-01753-5; OCLC 58053128
Titsingh, Isaac. (1834). Nihon Odai Ichiran; ou, Annales des empereurs du Japon.  Paris: Royal Asiatic Society, Oriental Translation Fund of Great Britain and Ireland. OCLC 5850691
Varley, H. Paul. (1980). A Chronicle of Gods and Sovereigns: Jinnō Shōtōki of Kitabatake Chikafusa. New York: Columbia University Press. ISBN 9780231049405; OCLC 6042764

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