The Illuminati are the top players on the International playground, basically belonging to the thirteen of the wealthiest families in the world, and they are the men who really rule the world from behind the scenes (yes, they are mostly men, with a few exceptions). They are the REAL Decision Makers, who make up the rules for presidents and governments to follow, and they are often held from public scrutiny, as their action can't stand being scrutinized. They are connected by bloodlines going back thousands and thousands of years in time, and they are very careful with keeping those bloodlines as pure as possible from generation to generation. The only way to do so is by interbreeding.