The sign of X is universally recognized as the sign of kingship.

E.g. did the faraohs in ancient Egypt had their arms crossed over their chests when they were mummified.

More close to Easter Island there was the Inca Empire, which was conceived as consisting of four parts (suyus) - explaining why the Inca Empire was called Tawantinsuyu = The Four Suyus.

The Inca ruler was located in the middle and he surely was considered as the personification of his empire. Therefore the four suyus were his four members - as I see it.

I will not go further now and here about this subject, as I feel that there are enormous amounts of interesting and relevant information concerning this X available in all kinds of sources and all kinds of contexts.