Gustavus Adolphus (1594--1632) dominated his age: he made Sweden the leading power of Northern Europe, was the principal upholder of the Protestant cause in the Thirty Years War, and was a great administrator as well as a brilliant soldier. His toleration and reforms helped define the development of the modern state. This concise study of his career, by the doyen of modern historians of the North, appeared in 1973. Long unavailable but now revised, expanded, updated and reset, it makes a welcome return in Profiles in Power.