Why do you eat moon cakes on Mid-Autumn Festival? What's the story?

According to legend, in the Tang Dynasty, Tang Gaozu Li Yuan (also said to be Emperor Taizong Li Shimin) conquered the northern Turkic, pacified its repeated violations, and made its general Li Jing personally lead the troops to the frontier fortress. As a result, he repeatedly made meritorious military service and returned to Beijing triumphantly on August 15. In order to celebrate the victory, guns were fired and music was played inside and outside Chang 'an, Kyoto, and the soldiers and civilians reveled all night.

At that time, a Tubo went to Chang 'an to trade, and specially presented round cakes to the emperor to celebrate the victory. Gaozu was overjoyed. He took a beautifully decorated cake box, took out colorful round cakes, pointed to the bright moon hanging in the sky and said, "Hu cakes should invite toads", and then distributed them to civil and military officials. Since then, the custom of eating moon cakes on Mid-Autumn Festival has been handed down.

Related stories:

A long time ago, there were ten suns in the sky, which dried up the earth and dried up the sea. People can't live happily without water. The hero Hou Yi shot down nine suns in one breath and saved people. So the Queen Mother gave the elixir to Hou Yi, and Hou Yi gave it to his wife Chang 'e for safekeeping.

A bad man tried to steal the elixir of life when Hou Yi was not at home. In order to protect it, Chang 'e swallowed the elixir of life in one gulp. Immediately, she was as light as a swallow and flew.

She was reluctant to leave Houyi and lived in the moon closest to the ground. There is only a little rabbit on the moon with Chang 'e. When people know this, they put fruits and biscuits in the yard to pray for the early reunion of Hou Yi and Chang 'e, and for the peace and happiness of their families. Every year, the custom of appreciating the moon and Yue Bai in Mid-Autumn Festival has been handed down.