The Iron Sheik is a (presumably Arabic) Spark of legendary renown, as well as a good friend and former traveling companion of The Heterodyne Boys and Baron Klaus Wulfenbach (and maybe Trelawney Thorpe). Little is known about him, but he is a popular figure in adventure and with and he from The Heterodyne Boys and the Race to the West Pole. Oh, and he thought it was a good idea to send his younger son, Z, to live on Castle Wulfenbach for lessons in and possibly . Well, that last one seems to be .
While the Heterodyne Boys have disappeared and Klaus has been too busy playing
kindergarten teacher tyrant to the sparks and royal houses of Europe to , it is unclear what exactly the Iron Sheik has been up to since The Other War, although there's been mention made of an which may have conquered Egypt, so it sounds like he may have done all right for himself. He apparently still trusts Klaus as a good role model for his children, so whatever worried Barry seems not to have fazed him in the least.
Though the Iron Sheik's real name is unknown, based on Arabic naming conventions and Z's full name, Sulimân al-Sinhâjî seem like a safe bet for his given and family names. Whether he too has a couple of other names sandwiched in between is anybody's guess.