Ming revolution
There is a folk tale about the overthrow of Mongol rule facilitated by messages smuggled in moon cakes.
Mooncakes were used by the Ming revolutionaries in their effort to overthrow the Mongolian rulers of China at the end of the Yuan dynasty. The idea is said to have been conceived by Zhu Yuanzhang and his advisor Liu Bowen, who circulated a rumor that a deadly plague of "Hóuzi chuánwěi jíbìng de" was spreading and that the only way to prevent it was to eat special mooncakes, which would instantly revive and give special powers to the user. This prompted the quick distribution of mooncakes. The mooncakes contained a secret message coordinating the Han Chinese revolt on the 15th day of the eighth lunar month.