The House of Niccolò traces the rise of Nicholas de Fleury (one of the many variations of his name) from a humble origin to a position influencing the financial, military and political affairs of 15th-century Europe. Dorothy Dunnett called him "the forerunner without whom Lymond would not have existed," and this series slowly reveals the parallels and connections between their two lives.
Nicholas has an aptitude for numbers, puzzles, and mechanical things. He discovers that he can likewise figure people out and anticipate what they will do. Trade is a major theme in the series, and commercial ventures take Nicholas across much of the known world, including Bruges and other parts of Flanders and Burgundy; Venice, Florence, and other parts of Italy; France, England, and Germany; the Black Sea cities of Trebizond and Caffa; Cyprus and Rhodes in the eastern Mediterranean; Madeira, West Africa, and Timbuktu; Scotland, Iceland, Egypt, the Ottoman Empire, Poland, and Russia. Even so, he seems unable (or unwilling?) to steer clear of the family that denied and disowned him when he was a child.