Abu-Lu'lu'ah was a Persian Zoroastrian slave who assassinated the Muslim ruler, or caliph, Umar al-Khattab in CE. His original name was Pīrūz (Arabicized: Firuz)The Origins and Early Development of Shi`a Islam http://www.karbala-najaf.org/shiaism/058-079.htm p.58-079.