Hokuriku Chotei (The Imperial Court In The Hokuriku Region) (北陸朝廷)
"Hokuriku Chotei" refers to the Imperial Court that is deemed to have existed during the period of Northern and Southern Courts in the present Hokuriku Region, which was backed up - and was claimed to have legitimacy - by warlords taking the side of the Southern Court.
Hokuriku Chotei Theory
Defeated in the Battle of Minato-gawa River, Emperor Godaigo fled to Mt. Hiei and had negotiations for peace with Takauji ASHIKAGA who entered Kyoto. Having a sense of crisis about this situation, Yoshisada NITTA and Yoshisuke WAKIYA had Imperial Prince Tsuneyoshi and Imperial Prince Takayoshi over them, and went to the Hokuriku Region in November 1336. Around this time, Emperor Godaigo had many of his Imperial Princes, including the above-mentioned two, go down to local provinces. Vol. 17 of "Taiheiki" (The Record of the Great Peace) says Emperor Godaigo transferred the Imperial Throne to Imperial Prince Tsuneyoshi around then; Emperor Godaigo made peace with Takauji ASHIKAGA and went down Mt. Hiei, but afterward, Emperor Godaigo left Kyoto and newly established the Southern Court for himself in Yoshino Province, and so, the transfer of the throne became meaningless.
In "Shirakawa Monjo" (Transcriptions of Shirakawa Yuki's Family Documents), there still exist transcriptions whose contents are the transmission of "rinji" (the Emperor's command), which were issued from Yoshisada NITTA and Yoshisuke WAKIYA to Munehiro YUKI on December 23, 1336, and on March 19, 1337. And there also exists a letter which conveyed the commendation of Emperor for the distinguished war service. The letter was sent from Yoshisada NAKANOIN (the provincial governor of Echizen Province) to Kuro Yorikazu TOKUE in A.D. 1346 (or the second year of "Hakuroku," which was used as the name of the era in Hokuriku Chotei), and the letter is now called "Tokue Monjo" (the Tokue Family's Documents), or "Hakuroku ninen Yukisada Hoshittatsujo" (The Commendation of the Emperor, conveyed by Yukisada in the second year of Hakuroku). Based on these historical sources, the Imperial Court is deemed to have existed in the present Hokuriku and Tohoku Regions at that time, which was backed up by the warlords taking the side of the Southern Court.
Hokuriku Chotei that was claimed to have existed by Yoshimasa MIURA
Yoshimasa MIURA called himself Emperor (he was just one of those who did the same thing) because, Miura claimed, Imperial Prince Takayoshi had been the Emperor of Hokuriku Chotei and he himself was the Takayoshi's descendant.