The Sun Cross is one of the oldest religious symbols in the world, appearing in Asian, American, European, and Indian religious art from the dawn of history. Carvings of it were found in 1980 on the bases of bronze-age burial urns at Southworth Hall Barrow, Croft, Cheshire, England - these urns date back to circa 1440 BC.
Different cultures have had their own names for their Sun deity, which unsurprisingly have been associated with the same symbol. Hence all the different names which represent the same magnificent Golden Sphere in the sky that provides heat and light, enabling things to grow. It represents the solar calendar- the movements of the Sun, marked by the solstices. Sometimes the equinoxes are marked as well, giving an eight armed wheel. The swastika, which is still used by Buddhists and was hijacked by Nazi Germany, is also a form of the Solar Cross. The Ancient Greeks reasoned that there were more things to life than just heat and light, and realised there must be an even greater God who had made all this possible – by the time of Plato they would refer to it as the ‘Sun behind the Sun.’
As we know, the Cross is considered these days to be quintessentially Christian. An interesting variation of the Solar Symbol is their ‘Ichthus Wheel,’ combining the symbolism of the fish with that of the Christ monogram (‘Chi-Rho’), or Labarum. One may also find an anchor in the design. This was accomplished by overlaying the Greek letters IXOYE (iota chi theta upsilon sigma) in such a way that the resulting symbol resembles a spoked wheel. The image of the wheel was already a fairly common emblem of Jupiter, and thus could be used without drawing undue attention to the outlawed faith in the early Christian Era.
I particularly like the emblem of the Etruscan God Ixion, who was depicted superimposed on a Solar Cross – see above right image (note the similarity to the Chi-Rho cross).
Credit for Images
TOP LEFT: https://upload.wikimedia.org/wikipedia/commons/thumb/9/98/Crossed_circle.svg/1200px-Crossed_circle.svg.png
TOP RIGHT: http://symboldictionary.net/library/graphics/symbols/glossaryixion.jpg
BELOW: [IXOYE] http://symboldictionary.net/?p=2963