The Arthur legend is often about a lost world where chivalrous knights and mighty kings were noble, romantic, etc.
White's version is much darker. Merlin lives backwards and makes reference to an Austrian who will plunge the world into chaos and he turns Arthur (Wart) into animals to teach his the importance of seeing middle ground... and that might is not right... for example, when he is turned into an ant, over ever entrance is written "everything not forbidden is compulsory" and Wart doesn't like it (though he doesn't know why). Also, the ant's language is reduced to "done" or "not done" so although Wart wants to ask if they are slaves and if they are happy, he can't because there are no words to ask the question that they would understand. Also, there are idealized pop songs (brainwashing) played at all times and Wart is given an "identity": 42436/WD like a prisoner.