Machiavelli.

Nicolo Machiavelli wrote "The Prince", about how a prince can rise in power, and maintain his power. Machiavellians tend to use a ruthless philosophy of hurting people before the people can hurt them, and hurting them bad enough to not have to worry about revenge being plotted against them. Their methods are ruthless and immoral, but by setting a goal, making plans, and getting rid of anything in their way, they can stay in power …

…thy angry soul/Thou drown the sad remembrance of those wrongs/Which thou supposest I have done to thee," [IV,iv,250-253]. Richard had no conscience whatsoever, he lied about people, and didn't ever let off his guard, or stop plotting to keep in power. Although many of Richard's methods where Machiavellian, he killed one or two people at a time instead of having a mass killing. He did a little bit more individual plotting.