<p>Jules Dufour, a Jewish banker in Paris, devised a complex scheme (involving his son Armand) to save the family and the family bank from liquidation when Germany invaded France in 1940. The scheme worked, but it needed the co-operation of Sheikh Ghassan, the Amir (ruler) of Abdali Umm-Qasr, an oil-rich French dependency. Ghassan had reason to believe that, at the end of the war, his country would gain its independence and control the oilfield. ...