 In 1029 , Sigtrygg 's son Olaf was taken prisoner by the new lord of Brega , Mathghamhain Ua Riagain . Sigtrygg was forced to pay a ransom of 1 @,@ 200 cows , 140 British horses , 60 ounces of gold and of silver , " the sword of Carlus " , the Irish hostages of Leinster and Leath Cuinn , " four hostages to Ua Riagain as a security for peace , and the full value of the life of the third hostage . " An additional 80 cows " for word and supplication " were to be paid to the man who entreated for Olaf 's release . The incident illustrates the importance of ransoming noble captives , as a means of political manipulation , increasing one 's own revenues and exhausting the resources of one 's foes . 
