William the Conqueror (en Inglés) - Edward A. Freeman

In this classic biography of William the Conqueror, Edward Freeman frames the first Norman king of England as a tireless force who, rather than crush the native culture of the kingdom he had just conquered, preserved and exploited it to secure his rule and reward his followers.

But crush his opponents he did, whether as the duke of Normandy or king of England. Being a brutal overlord in an age where that was nothing uncommon helped him achieve his aims and change the course of history.