Simple

Japanese: 簡狄 - かんてき

…The Book of Rites, Monthly Orders, describes a ritual in which, in the mid-spring month, when the swallow arrives, Gao He is offered a large cage (ox, sheep, and pig) and the emperor and his concubine exchange bows and arrows in front of him. Its origin can be found in the legend of the founder of the Yin dynasty, in which Jian Di drank the egg of a swallow, became pregnant, and gave birth to a son, so the snake was worshiped. There is also a legend about Emperor Kansheng, Jiang Yuan, the mother of Zhou's Hou Ji, who became pregnant after stepping on a giant's footprint. …

From 【Kei】

…A legendary figure who is said to be the ancestor of the ancient Chinese Yin royal family. It is said that Jian Di, the second wife of Emperor Huangdi's great-grandson, Emperor Huangdi, ate a swallow's egg and became pregnant, and gave birth to the baby. During the reign of Emperor Shun, he assisted Yu in flood control, was appointed as the Minister of Education, educated the people, and was given the title of Governor of Shang (Shangqiu County, Henan Province). …

*Some of the terminology explanations that mention "Jian Di" are listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

Japanese:

…《礼記（らいき）》月令（がつりよう）に，仲春の月，玄鳥(燕)が至るとき，大牢(牛，羊，豕)を供えて高禖を祀り，天子と後宮夫人とがその前で弓矢を授受する儀礼をしるす。その起源は殷の始祖説話に，簡狄（かんてき）が玄鳥の卵を飲んで妊（はら）み，契（せつ）を生んだのでこれを祀ったという。周の后稷（こうしよく）の母姜嫄（きようげん）にも，巨人の足あとを践（ふ）んで妊んだという感生帝説話がある。…