It is believed that this event has become widely held because of the custom where July 15 (in the old calendar) was called chugen-setsu (or chugen), and on this day, secular people other than priests conducted a memorial service to their ancestors, offering food and lighting lanterns.
この行事が一般に広がったのは、仏教者以外の人々が7月15日(旧暦)を中元節（中元）といって、先祖に供物し、灯籠に点火して祖先を祭る風習によってであろう。