Domingo Montoya was a master swordsmith, and the father of Inigo Montoya. Domingo remained obscure because he disliked dealing with the stupid rich and privileged.
When Count Tyrone Rugen, a nobleman with a six-fingered right hand, asked him to forge a sword to accommodate his unusual grip, Domingo poured his heart and soul into the project for a year until it was done.
When Rugen returned, he reneged on his promised price, willing to pay at only one-tenth. Thus, Domingo refused to sell him the sword, not as a matter of money, but because Count Rugen could not appreciate the great work of the sword. He proclaimed that the sword would now belong to Inigo. Angered, Count Rugen slashed him through the heart, thus ending his life.
Inigo spent the next 20 years looking for Rugen to avenge his father's death. Praying to his father for guidance, Inigo eventually ended the Count's life, avenging Domingo's murder.