Percy de Somerville, the Comte and later Duc de Somerville, is the Royal Commander of Terre d'Ange at the start of the series. He serves faithfully in the Battle of Three Princes and the Skaldi invasion, but he plots with Melisande Shahrizai to steal the throne after she blackmails him. He is kin to Queen Genevieve de Somerville and counted as a Prince of the Blood. Ghislain de Somerville is his son.
At some point he wrote a treatise on the propagation of apple trees that Moirin mac Fainche read long after his death.