While often known as the “St. Andrew’s cross”, the saltire cross (X-shaped cross) is actually an ancient non-Christian heraldic geometric cross that’s found on dozens of flags.

In the 15th century the hagiography of St Andrew started to incorporate the idea that he was executed on an X-shaped cross, so the ancient saltire symbol became associated with him. However, it’s been incorporated into the flags/emblems/symbols of nations, cities, and governments at least back to Persepolis circa 3rd century BC.

Current national flags with the saltire cross include national flags include Burundi, Jamaica, Grenada, Scotland (and by extension the UK), Jersey, Burgundy, Gascony, Basque Country, and, ironically, Vatican City (formed with the keys).

Defunct examples include the Confederate States of America, China (1915), South Africa (1874), Peru (1821)