This variant on the Greek cross looks like a large “X,” and represents in Christianity the initial of Christ, the Greek letter chi. It is the original Christian cross, predating the Latin cross by several hundred years.
It is most often referred to as the Cross of St. Andrew, after the manner of the Saint’s supposed crucifixion.
As St. Andrew is the Patron saint of Scotland, his cross has become a symbol of Scotland, appearing on flags and other emblems.
St. Andrew with his cross