gengō

The term "Gengō" (元号) refers to Japanese era names, which are used to number years in historical Japanese calendars. These era names, or nengō, were adopted from China and first officially used in Japan in 645 CE with the "Taika" era. The system evolved over time, with periods of dual eras during imperial splits and the eventual adoption of the Gregorian calendar in 1873, though the nengō system continues alongside it.1

The Heian period (794–1185) was a significant era in Japanese history, named after the imperial capital moved to Heian-kyō (modern Kyoto). This period saw the flourishing of courtly culture, with advancements in art and literature, most notably Lady Murasaki Shikibu's novel The Tale of Genji. Religiously, both formalistic Buddhist sects and those emphasizing simple faith gained popularity. The late Heian period was marked by social upheaval and armed conflict between the Taira and Minamoto clans, ultimately leading to the establishment of warrior government.23