Language is a great power. The biggest and more effective way to manipulate society is the using the language power. The history knows a lot of examples when political regimes recognize it and use this power for their goals. I think, that distinction is just in the ways how to use it, not what kind of political regime it is, democracy or totalitarian.
The great example of language power we could observe in the book of George Orwell "1984". The government of Oceania control the people using the language and information that is profitable for their political ideas. They used high technology to control life style of their citizens and for take care of their loyalty they use propaganda, what is very effective brainwashing. They create Newspeak, language of the party, language that was devised to meet the ideological needs of Ingsoc. "The purpose of Newspeak was not only to provide a medium of expression for the world-view and mental habits proper to the devotees of Ingsoc, but to make all other modes of thought impossible." Appendix, pg. 303
The government publish the Newspeak Dictionary where change the meaning of a words and remove important moments from the vocabulary with hope to predict anti-social thoughts before it could enter a person's mind. They fear power that has these words and even can not allow their using. The consequences that could follow after recognition of meaning may contribute to the revolution. That is why ,it is easy to remove vocabulary for revolution, there can be no revolution.
More over, using the language power the government could provide information that is not adequate reality, in other world the distorted and false. The language could tell the try about history of the country. The sources of history include books, printed documents, archival records, personal papers. That is why every totalitarian regime do everything for different interpretation or ever destruction the history using the language that...