The Sword and the Scimitar - David Ball

Nico and Maria, Maltese brother and sister, are separated when young Nico is abducted by Moorish slavers. Taken to Algiers to be the personal slave of a wealthy merchant, he becomes a pawn in household politics and sets out to escape. Extraordinary events lead him to the court of Suleiman the Magnificent, Sultan of the Ottomans.
 
Stranded alone on Malta, Maria must learn to survive helped only by a group of Jewish refugees. A sweeping historical epic set against the backdrop of the desperate conflict between Christian Europe and the Islamic Ottoman Empire, The Sword and the Scimitar vividly portrays an irresistible and fast-moving world of adventure, war, treachery and love.