What cousin of Herman I, Duke of Swabia also had a chance to rule the Duchy of Franconia?
Herman I, Duke of Swabia Herman I (died 10 December 949) was the first Conradine Duke of Swabia (from 926), the son of Gebhard, Duke of Lorraine, and a cousin of King Conrad I of Germany.
Frederick, Duke of Lower Lorraine Frederick, Duke of Lower Lorraine, also known as "Frederick of Luxembourg" (  1003 – 18 May 1065) was the count of Malmedy from 1035 and Duke of Lower Lorraine from 1046. He was a younger son of Frederick, Lord of Gleiberg.