Gemini - Dorothy Dunnett

GEMINI represents the final appearance of Nicholas de Fleury, known in the first book of this series as a carefree 18-year-old apprentice in Flanders. Now in his thirties, despite his enemies, his flair for numbers has launched him on a chaotic career: as a mercenary soldier; as a merchant banker; and now as a man who could find a place in almost any of the kingdoms or republics that made up 15th century Europe.
But where? First, he has to go back to Scotland, although he knows men wait there to kill him and his beloved family. If he survives, he must make a choice. He does not know that before that can happen, every skill he ever had will be tested.