Capitalize proper nouns and words derived from them. Two examples!
Texas (state) - Texan (relating to the state of Texas or its inhabitants)
Hungary (country) - Hungarian (relating to Hungary or its people)
Peru (country) - Peruvian (relating to Peru or its people.)
Geoffrey Chaucer (English writer) - Chaucerian (relating to Geoffrey Chaucer or his works)
Niccolò Machiavelli (Italian political philosopher) - Machiavellian (relating to Machiavelli or his political theory)
Franz Kafka (German-language author) - Kafkian or Kafkaesque (relating to Franz Kafka or his novels and short stories.)