The Four Symbols and Twenty-Eight Mansions 四象二十八宿

In ancient China, the twenty eight stars near the ecliptic were called "the twenty eight mansions", which were used to mark the traveling positions of the sun and the moon as wells as to detect the time and seasons. In order to make it easy for memorizing, people divided the sky ecliptic into four regions, each assigned with an animal to stand for it. They are Azure Dragon on the east, White Tiger on the west, Vermilion Bird on the south and Black Tortoise on the north. Each region contains seven mansions. The four creatures are collectively called "the Four Symbols".

The Four Symbols and Twenty-Eight Mansions were formed in a gradual process. In the archeological findings from the Tomb of King Yi of Zeng, there's a lacquer-painted wardrobe with the patterns of the Four Symbols and Twenty-Eight Mansions, indicating that Chinese people had rich astronomical knowledge over 2,000 years ago.

The Four Symbols evolved with the changes of the Taoist divinity system. In Taoism, the indigenous religion of China, the Four Symbols are also the four guardian gods defending the gates of Taoist temples.