The Flag of Scotland is a white saltire, a crux decussate (X-shaped cross) representing the cross of the Christian martyr Saint Andrew, the patron saint of Scotland, on a blue field. It is named the Saltire or the Saint Andrew's Cross. In heraldic language, it may be blazoned Azure, a saltire argent.
According to legend, in 832 A.D. King Óengus (II) (or King Angus) led the Picts and Scots in battle against the Angles under a king named Athelstan near modern-day Athelstaneford in East Lothian. King Angus and his men were surrounded and he prayed for deliverance. During the night Saint Andrew, who was martyred on a saltire cross, appeared to Angus and assured him of victory. On the following morning a white saltire against the background of a blue sky appeared to both sides. The Picts and Scots were heartened by this, but the Angles lost confidence and were defeated. This saltire design has been the Scottish flag ever since.