Why is purple king?

You should be able to find your answer from this.

The Forbidden City was formerly called the Forbidden City. From the fourth year to the eighteenth year of Yongle in Ming Dynasty, Zhu Di, the founder of Ming Dynasty, began to build it, and 24 emperors were in power here after Ming and Qing Dynasties. The Forbidden City is a royal palace with red walls, yellow tiles and golden walls. Why is it called the Forbidden City? There are roughly three kinds of views as follows: one thinks that this is related to the allusion of "purple gas came from the east" in ancient times. Legend has it that Lao Tzu went out to Hangu Pass, and purple gas came from east to east, which was seen by the keeper. Not long after, Lao Tzu came riding a green cow, and the keeper knew that this was a saint. The gatekeeper asked Lao Tzu to write the famous Tao Te Ching. Therefore, purple gas is considered to have auspicious meaning, indicating the emergence of sages and treasures. Du Fu's poem "Autumn Prosperity" says: "Looking at the Yaochi in the west, the Queen Mother will descend, and the purple gas will fill the customs in the east." Since then, the ancients have called auspicious qi Ziyun, the legendary immortal's place of residence as Zihai, the immortal as Ziquan, and the path outside the suburbs as Zimo. Purple gas comes from the east, symbolizing auspiciousness, which shows that the "purple" in the Forbidden City is well-known. The place where the emperor lived was heavily guarded and inaccessible to ordinary people, so it was called the Forbidden City.

Another view is that the origin of the Forbidden City is related to superstitions and legends. The emperor pretends to be the son of the emperor of heaven, that is, the son of heaven. Tiangong is the place where the Emperor of Heaven lives, and naturally it is the place where the Emperor of Heaven lives. "Guangya Interpretation of Heaven" says: "The Heavenly Palace is called the Purple Palace." Therefore, the palace where the emperor lived was called the Purple Palace. There is also a saying that the origin of the Forbidden City is related to the ancient "Imperial Wall" theory. In ancient times, the stars in the sky were divided into three walls, twenty-eight stars and other constellations by astronomers. Three walls refer to Taiwei Wall, Tianshi Wall and Ziwei Star Wall. The Ziwei Xingyuan is called the Emperor, and it is located in the center of Sanyuan. Purple MSI is the Big Dipper, surrounded by stars. In ancient times, there was a saying that "the purple is in the middle" and that "the emperor of peace sits in the middle, and the officials of the Qing Dynasty are divided into four seas".

Since the ancients compared the Emperor of Heaven to the Purple Star Garden, the Purple Star Garden became the land of the emperor's pole. Therefore, the imperial palace was called Purple Pole, Purple Forbidden Garden and Purple Forbidden Garden. The saying of "Purple Forbidden Garden" existed as early as the Tang Dynasty. The Forbidden City in Beijing covers an area of 1,87 mu, with a length of 961 meters from north to south, a width of 753 meters from east to west and a circumference of about 7 Li. There are more than 9, halls and houses, and the surrounding walls are more than 1 meters high. Calling this imperial city the Forbidden City is not only worthy of the name, but also contains the meaning of the city of the son of heaven.

Looking at the buildings in the Forbidden City, the lofty and great Hall of Supreme Harmony, which symbolizes the "heaven", is located in the middle of the Forbidden City and is the highest and most prominent place. It symbolizes the close connection between heaven and earth, and the two palaces of Kunning. On both sides of them, there are two doors, namely, Rijing and Yuehua, which symbolize the sun and the moon. And the array buildings outside the sixth house, which symbolize the twelve stars, represent the stars in the sky. This is a symbolic building complex.

The old name of the Forbidden City, the Forbidden City, can be said to be highly unified in naming and architectural design from the perspective of "Xingyuan".