The swans are flying. According to "Historical Records", in the first year of the Han Dynasty (100 BC), Emperor Wu of the Han Dynasty sent Su Wu as an envoy to the Xiongnu. He was detained for a long time and imprisoned in the bitter cold of Beihai (today's Lake Baikal). Strip for many years. Later, the Han Dynasty sent envoys to ask the Xiongnu to release Su Wu, but the Xiongnu Chanyu lied that Su Wu was dead. Chang Hui, who was on an envoy to the Xiongnu with Su Wu, met the Han envoy secretly and told Su Wu that he was not dead, and asked him to tell Shan Yu: The emperor of the Han Dynasty was hunting in Shangli Park and shot a wild goose with a piece of silk tied to its foot. , it said that Su Wu was in a large lake. In this way, the Xiongnu Chanyu could no longer pretend that Su Wu was dead, so he had to release him back to the Han Dynasty. There is also a popular story among the people: Xue Pinggui of the Tang Dynasty was away on an expedition, and Wang Baochuan stayed at the cold kiln for more than ten years with determination. One day, Wang Baochuan was picking wild vegetables when he suddenly heard the calls of swan geese in the sky, so he asked to pass a letter to Mr. Pinggui on his behalf. However, he could not find pen and ink for a while. In desperation, he tore off his skirt, bit his fingertips, and wrote a letter of blood and tears. , expressing feelings of loyalty to love and longing for the reunion of husband and wife. As these stories spread and became legends through the ages, Hongyan also became a good name for the postman.
“Swan geese pass the message” is an ancient Chinese folklore, because swan geese are migratory birds that migrate regularly, keep time, gather in groups, and are highly organized. The communication methods of the ancients were relatively backward at that time, and they were eager to send letters and communicate information through this migratory bird that was equipped with "benevolence, justice, etiquette, wisdom and trust". According to historical records, Su Wu, who was on an envoy to the Xiongnu during the reign of Emperor Wu of the Han Dynasty, was detained by the capricious Chanyu for 19 years. After Emperor Zhao came to the throne, he learned the truth and asked the newly sent Han envoys to tell Shan Yu: "The emperor of the Han Dynasty hunted a wild goose coming from the north. There was a letter tied to the goose's leg, which said that Su Wu was in Beihai (now Lake Baikal). ) Shepherd." Chanyu saw that Tao had revealed the secret and could not hide it, so he let Su Wu return to Han. This is where the term "Hongyan Chuan Shu" comes from.