Andrew is the First-Called in the Orthodox reckoning — the first of the Twelve to follow, and the one who brings his brother Peter. The tradition has him crucified at Patras on a diagonal cross, said to have been his own request, since he would not die in the manner his master had. That diagonal is the saltire, and it is on the flag of Scotland, whose patron he became, and through it on the union flag and half a dozen others.
OrthodoxWiki · Apostle Andrew