Edit: False info apparently.

"The I Ching is the oldest book in the world; its basic structure developed in pre-history. Confucius, in his Great Commentary, credited the pre-historic Three August Ones and the Five August Emperors with ordering the world according to its precepts. From the Chou Li, or Book of Chou Rites dating from around 1000 BCE, we learn that the Book of the I was only one of three prophetic or divinatory books known to the ancient Chinese. The Li Chi, one of the Five Classics, informs us that turtle shells were in common usage in divination using a system derived from Fu Hsi's trigrams. All that we can really know of its origins is that by the 12th century BCE, the oracle had taken its basic form of 64 binary hexagrams.

Apparently, up to this point, no recognized interpretations of the patterns existed. Each practitioner was free to interpret the patterns of the hexagrams in their own way. However, around the middle of the 12th century BCE, the late Shang dynasty deposed and imprisoned one of their dependents, King Wen. While in prison, King Wen turned his attention to writing descriptions, or judgments, on the 64 hexagrams. By careful use of the ideas revealed in his study, King Wen was able to affect his release and the re-instatement of his kingdom. Perhaps for this reason, his judgments have ever since been seen as definitive."

Traditionally it was believed that the principles of the I Ching originated with the mythical Fu Xi

In Chinese mythology, Fu Xi or Fu Hsi mid 29th century BCE, was the first of the Three Sovereigns of ancient China

Ningishzida is a Mesopotamian deity of the underworld. His name in Sumerian is translated as "lord of the good tree" by Thorkild Jacobsen.

In Sumerian mythology, he appears in Adapa's myth as one of the two guardians of Anu's celestial palace, alongside Dumuzi.