The Scottish National Flag, known as the Saltire or St. Andrew's Cross, features a white diagonal cross on a blue background. This design represents the patron saint of Scotland, St. Andrew, who was crucified on a cross shaped like the one depicted on the flag. The blue color symbolizes the sky and the sea surrounding Scotland. The flag's origins date back to the 9th century, making it one of the oldest flags in the world. It was officially adopted as the national flag in 2003, although it has been used for centuries. The Saltire is a prominent symbol of Scottish identity and pride.