The Name “Excalibur” was first used for King Arthur’s sword by the French Romancers. It was not the famous “Sword in the Stone” (which broke in battle), but a second sword acquired by the King through the intercession of his druidic advisor, Merddyn (Merlin). Worried that Arthur would fall in battle, Merlin took the King to a magical lake where a mysterious hand thrust itself up from the water, holding aloft a magnificent sword.
It was the Lady of the Lake offering Arthur a magic unbreakable blade, fashioned by an Avalonian elf smith, along with a scabbard which would protect him as long as he wore it.
Excalibur Stolen by Morgan le Fay
Towards the end of his reign, during the troubled times of Medrod’s rebellion, Excalibur was stolen by Arthur’s wicked half-sister, Morgan le Fay. Though it was recovered, the scabbard was lost forever. Thus Arthur was mortally wounded at the Battle of Camlann. The King then instructed Bedwyr (or Girflet) to return Excalibur to the lake from whence it came.