Yarrow derived its Latin name (Achillea) from the Greek hero Achilles, the son the Sea-Goddess Thetis and the mortal King Peleus. Thetis, attempting to make her son invulnerable, dipped him into the river Styx. But afraid to let the infant go completely, his ankles remained vulnerable where his mother had held him, the part that has become known as the ‘Achilles heel’. She also wanted to make him immortal by the power of fire, but Peleus disturbed her in her ritual and so she fled back to her father, leaving the infant in Peleus’ hands.
Peleus gave him to Chiron, the centaur, who had a great reputation for educating young boys in the art of archery and healing. And so, Achilles went on to become one of the greatest and “almost” invincible warriors, but in the end he died of a mortal wound to his Achilles heel. He was a great student of the healing arts though and Yarrow was his special ally. He used it to staunch the wounds of his fellow soldiers, which is how yarrow became known as ‘Militaris’.