From Wikipedia, the free encyclopedia
A saltire, Saint Andrew’s Cross, or crux decussata (though it is never called the last in heraldry), is a heraldic symbol in the form of a diagonal cross or letter X. Saint Andrew is said to have been martyred on such a cross. It forms the national Flag of Scotland, the Flag of Jamaica and appears on many other flags, arms and seals. It is also used as a traffic sign.
The saltire has been around for a long time on flags, coins, and documents signed by illiterates. It is nothing more than an “X”, but down through history has been used to represent ideals which have caused more hate and discontent, and killed more people than any square, circle or triangle. 
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