During Charles's rule the Spanish Empire was tremendously expanded in the New World. In Italy, Spanish power had become paramount. Even England seemed about to fall to Spain through Philip's marriage, and Charles's own marriage with Isabella of Portugal brought the Portuguese crown to Philip in 1580. Yet Charles failed in his purpose to return the Protestants to the Roman Catholic Church, and the human and financial cost of constant warfare drained Spanish resources; moreover, Charles's hopes for a universal empire were thwarted by the political realities of Western Europe. His integrity, strength of will, and sense of duty were conspicuous. His appearance has been made familiar by two portraits by Titian.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.