"Study power centers to understand history Holland and Sandbrook argue that civilizational change is best understood through the centers of power that drove it. They noted that "the most dramatic periods of history are often those at the heart of power, where successive rulers shape the destiny of entire civilizations over centuries." Studying who held power, how they acquired it, and how they lost it gives you a framework that applies to institutions, companies, and political movements today. Source: Tom Holland & Dominic Sandbrook, The Rest Is History, The Fall of the Roman Empire"