Rafael Sabatini 
Sea-Hawk 

The Sea Hawk is a novel by Rafael Sabatini, originally published in 1915. The story is set over the years 1588-1593 and concerns a retired Cornish seafaring gentleman, Sir Oliver Tressilian, who is villainously betrayed by a jealous half-brother. After being forced to serve as a slave on a galley, Sir Oliver is liberated by Barbary pirates. He joins the pirates, gaining the name "Sakr-el-Bahr" (The Hawk of the Sea), and swears vengeance against his brother.