Under the sign of the cross...

The cross, we learn, predates Christianity. Perhaps by 3,000 years. Ledge Altar, approximately as found.

As reconstructed:

It can even be tied to the great pyramid in Egypt!

Naturally, many of us have been aware of the cross-sun worship connection for decades.

When Constantine created his universal religion to unite the eastern (Byzantine) empire, his minions naturally brought this symbol along - replacing the two fish!

Even Papa Joe showed interest... as it was swept under the carpet.

An aside:

Above: Hitler's altar from His Berlin bunker.