I don't think there is an overall best example, just some really good examples. But I encourage you to look this thread over, as it does not only give a few examples, but explain the quote.

Some examples I can think of off the top of my head that may fit:

-Christianity vilifying other religions

-I am sure one could say Marie Antoinette may fit this in some way

-Pretty much any civilizations the Romans whomped on, like Carthage