The cousin of Mahomet, and one of his first followers at the age of sixteen, "a noble-minded creature, full of affection and fiery daring. Something chivalrous in him; brave as a lion; yet with a grace, a truth and affection worthy of Christian knighthood." Became Caliph in 656, died by assassination in the Mosque at Bagdad; the Sheiks yearly commemorate his death. See Carlyle's "Heroes."