Sentence:  ... this poor fool clung to Lear after he had given away his crown, and by his witty sayings would keep up his good humour, though he could not refrain sometimes from jeering at his master for  his imprudence in <WSD>uncrowning</WSD> himself, and giving all away to his daughters; 
Meaning of the word marked with <WSD> tags:  To deprive of the monarchy or other authority or status.