The chakra system originated in India between 1500 and 500 BC in the oldest text called the Vedas. Evidence of chakras, spelled cakra, is also found in the Shri Jabala Darshana Upanishad, the Upanishad Cudamini, the Yoga-Shikka Upanishad and the Shandilya Upanishad. According to the scholar Anodea Judith in her book The Wheels of Life, knowledge of the chakra system was transmitted through an oral tradition by the Indo-European people, also called the Aryan people. The chakra system was traditionally an Eastern philosophy until New Age authors, such as Anodea Judith, resonated with the idea and wrote about chakras, expanding older texts and making knowledge more accessible.
We'll discuss rainbow colors later in the post, but this was a modern, Western, New Age invention.