John Maurice of Nassau (1604-1679) was a Dutch military officer whose rise to power paralleled Dutch ascendancy in the Atlantic; his years as governor general of Netherlands Brazil marked the apogee of Dutch authority in South America.

John Maurice, who bore the title Count of Nassau-Siegen, was born on June 17, 1604, in the family castle at Dillenberg, Germany, scion of a famous European family. He received a thorough Calvinist education at Herborn, Basel, and Geneva. As early as 1620 he took up arms with the Protestants in the Thirty Years War; by 1626 he reached the rank of captain, and 3 years later he was promoted to colonel. Meanwhile, Dutch power was spreading through the North and South Atlantic. In 1630 Dutch arms triumphed in Recife, and the Dutch West India Company seized northeastern Brazil. From that powerful company, John Maurice accepted the post of governor general of Netherlands Brazil in 1636 and disembarked...