In 1368, Gensho SHU (Chu Yuan-chang), a leader of the Red Turban Rebellion, established a new era named "Kobu" starting with the year when he ascended to the throne in Nanjing City to found the Ming Dynasty, and later introduced a system of one era per Emperor.
1368年、紅巾の乱の首領朱元璋が南京市で即位して明を建国し、この年を「洪武元年」としたのち、一世一元の制を採用した。