Rongo rongo, the hieroglyphic script of Easter Island, has remained a mystery since its discovery. It has not been deciphered despite attempts by many linguists, and claims of success by some of them which invariably resulted in ridicule by peer scientists. Just 21 wooden tablets remain bearing the script.
A Hungarian scholar and author of several books, Wilhelm or Guillaume de Hevesy, in 1932 called attention to the apparent similarities between some of the rongo-rongo characters of Easter Island and those of the prehistoric script of the Indus Valley Civilisation, correlating dozens (at least 40) of the former with corresponding signs on seals from Mohenjo-daro. This correlation was republished in later books, for example by Z.A. Simon (1984: 95). Rongo-rongo may mean peace-peace, and the texts may record peace treaties, possibly between the long ears and the conquering short ears.
Alternatively, Steven Fischer interprets the rongo-rongo texts as litanies (so to speak) of mystical couplings between forces of nature. He suggests that the islanders developed the script after encountering writing when a Spanish ship called at Easter Island in 1770.