Famine of Yowa (養和の飢饉)
The famine of Yowa was a devastating famine that occurred in 1181. The famine occurred during a period of conflict (Jisho-Juei War), and there remain many historical documents which describe the situation in detail such as the Genpei Seisuiki (The Rise and Decline of the Minamoto and Taira clans) and the Hojoki (An Account of My Hut).
Summary
The rainfall in 1180 was well below normal, and crop yields decreased significantly due to drought, and the entire western Japan including Kyoto was plagued by famine the following year. Not only did many people starve to death, but also a large number of farmers fled from their homes. The local communities collapsed and chaos spread across the country.
Within Kyoto City
In the Hojoki, it is written that 42,300 people died in Kyoto City, and that the city was filled with corpses. It is also said that because there were so many dead people, it was impossible to hold a memorial service for each of them, monks at the Ninna-ji Temple went around the city to mark the Sanskrit character 'a' (,the first letter in the Sanskrit characters, 阿 in kanji) on the foreheads of the dead. This chaos is believed to have been a factor in making MINAMOTO no Yoshinaka's operations (raising of an army in 1180 and advancement to Kyoto in 1183) easier to carry out.