It is generally difficult to avoid going through Chinese when talking about Japanese, especially in terms of Kanji. The Japanese word Yomi, or in Kanji 黄泉, is actually derived from the same Chinese word 黄泉 (Pinyin: Huáng quán) with the literal meaning as "Yellow Springs" or "the springs within the yellow earth". Its original meaning was said to be groundwater, as the water pulled up from a deep well is often mixed with soil and looks yellow. One famous usage of its groundwater meaning was found to be in the Xunzi Encouraging Learning: "Earthworms lack the power of sharp claws or teeth, or strong muscles or bones, yet above ground they feast on the mud, and below they drink at the yellow springs. This is because they keep their minds on one thing. (蚓无爪牙之利,筋骨之强,上食埃土,下饮黄泉,用心一也。 )"
However, its meaning has long been changed to the Land of the Dead, same as the Japanese meaning. Its very famous as well as first appearance with this meaning associated with afterworld in Chinese texts was said to be in The Tso Chuan (The Zuo zhuan 左傳), in which Duke Chuang (or Zhuang) of Cheng (or Zheng) said to his mother Lady Chiang (or Jiang):"Not until we reach the Yellow Springs shall we meet again!" and afterwards regretted this decision, dug a deep tunnel and reached the springs, finally met his mother, and restored their relationship.
It also appears in "The Song of Everlasting Sorrow" (or Song of Everlasting Regret) by Bai Ju-yi as: He searched thoroughly up in the blue beyond, as well as down in the Yellow Springs below the earth, but did not spot her in the vastness of either place. (Another translation was: Up in heaven and down to hell he went. Both places were hazy, failing his intent. )(上穷碧落下黄泉,两处茫茫皆不见。), depicting the desperate searching for the beauty of the emperor.
Although different words, the Chinese 黄泉 can also be a synonym of Diyu (Chinese character: 地獄), a Chinese mythological concept translated as "Hell", or also "the Land of Dead". It also appeared in Japanese with almost the same meaning but was said to be associated to different religions with 黄泉 and was a much more complicated concept.
The Tso Chuan (Chinese characters: 左傳), also translated as The Zuo zhuan or Zuo Tradition based on different Pinyin, is said to be China's oldest work of narrative history. Its entries provide a year-by-year, often mouth-by-mouth, account of happenings in the various feudal states that made up the China of the time for the period from 722 to 468 BC, called the Spring and Autumn Period (Chinese characters: 春秋時期), when the area of northern and central China was divided into several feudal states of varying size. The Tso Chuan focuses primarily on political, diplomatic, and military affairs but also some economic and cultural developments as well.
Lady Jiang 姜 = Chiang = the mother who loves the little brother more
Lord Zhuang 莊公 = Chuang = the main character who defeats his little brother and swears that he will never meet his mother again
Duan 段 = Tuan = the little brother
Zheng 鄭= Cheng = the state/country
Our story occurred in State Cheng (or Zheng, based on different translation), around the middle area just below the Yellow River.
The Chinese story that Yomi appeared was the very first story noted in the book, the first year in the period of Lord Yin (隱公) at 722 BC.
In short, Lady Jiang, the mother of both Lord Zhuang and his younger brother Duan, favors the latter on account of Lord Zhuang's breech birth. She repeatedly plots with Duan to usurp Lord Zhuang 's position. Against all counsel to forestall the rebellion before it is too late, Lord Zhuang refused to act until Duan's rebellion is full-fledged. Then he crushes it and drives Duan into exile (one said that Duan died after war). The consequent estrangement from his mother, whom he vows never to see again until they reach the Yellow Springs (the underworld), is healed only when an ingenious border officer, Ying Kaoshu, suggests that he digs a tunnel and meet his mother here. By substituting the literal for the metaphorical meaning of "Yellow Springs", Ying Kaoshu brings about reconciliation without undoing Lord Zhuang's vow.
It illustrated that Lord Zhuang swore that he would never see his mother again until they reach the Yellow Spring/Land of the Dead, but then regretted saying so. Ying Kaoshu, who met the lord and by sharing his story, suggested Zhuang that he could actually dig a tunnel deep enough to reach the "Yellow Spring", and met Lady Jiang there so that he technically would not betray this oath. Lord Zhuang did so and recited a poem when he came into the tunnel, and the mother Lady Jiang also recited another corresponding poem when she met the lord, so that he finally reconciled with her. The last part was a "moral teaching" pattern that frequently occurring in these kinds of story.
*Comic book adapted from a novel called The Romance of the Eastern Zhou by Liu Tong