The Ringed Castle by Dorothy Dunnett

For the first time Dunnett's iLymond Chronicles/i are available in the United States in quality paperback editions.pFifth in the legendary iLymond Chronicles/i, bThe Ringed Castle/b leaps from Mary Tudor's England to the barbaric Russia of Ivan the Terrible. Francis Crawford of Lymond moves to Muscovy, where he becomes advisor and general to the half-mad tsar. Yet even as Lymond tries to civilize a court that is still frozen in the attitudes of the Middle Ages, forces in England conspire to enlist this infinitely useful man in their own schemes.