What god invented the rainbow?

Answer 1

In The Bible in the book of Genesis you can find that God created the rainbow as a promise to never flood the world again.

A Pagan Perspective: According to Greek Mythology, Iris is the Goddess of rainbows. She was also a messenger to the Olympians. She was sometimes also seen as the handmainden and personal messenger of the Goddess Hera. Her father was Thaumas- "the wonderous" was a marine god and her mother was Elektra- "the amber", who was a cloud nymph.

Answer 2

Scripture does not refer to it as a rainbow. God said "I do set my bow in the cloud" in Genesis 9:13. The sign of the bow ( a weapon of war) in the cloud signals peace. The Bible does not mention what year it was, only Noah's age at the time (Genesis 8:13).

Another Answer:

Some have dated the Flood beginning in the 2nd month, 17th day of BC 2327 and Noah's family exiting the Ark in the 2nd month, 27th day of BC 2326. It would have been shorthly thereafter that God made the Noahic Covenant and but a sign of His 'rainbow' in the sky (Genesis 9:13, NKJV).

Note: Exact terms are often dependent upon the translation in use.