One of the best-known thistle legends takes place in the mid 13th century during a surprise invasion by the soldiers of the Norse king, Haakon, at Largs (one of western Scotland's coastal towns).
The story has it that after coming ashore, this Viking force planned to creep up on the Scottish Clansmen and Highlanders and overcome them while they slept.
This amount of stealth required that they go barefoot - which proved to be their undoing!
Unfortunately for these unwary invaders, one of their soldiers bare feet came down hard on a Scottish thistle and his cries of shock and pain were enough to wake the sleeping Scots.
Leaping to their feet, the clansmen charged into battle and the rest, as they say, is history... and yes, the fiery Scots were victorious. -- Info found: Scottish at Heart