I would argue that any government that practiced slavery was doing what the government in Brave New World was doing, at least to some extent. What they were doing was trying to create castes of their own so that they would have slaves to do all the "dirty work" while other "higher" people could do more advanced stuff. Both groups would supposedly be happy.
I think you can argue that the Roman emperors did some things like the government in the book. In addition to slavery, they also gave the people all sorts of forms of entertainment (gladiators, etc) to keep their minds off any sort of rebellious thoughts. This is similar to how the government in the book wants people to always be having fun so they won't think.