Question: When did Manchu ethnicity become important again in the Eight Banners?
Sentence: It was in Qianlong's reign that the Qianlong Emperor, concerned about maintaining Manchu identity, re-emphasized Manchu ethnicity, ancestry, language, and culture in the Eight Banners and started a mass discharge of Han Bannermen from the Eight Banners, either asking them to voluntarily resign from the Banner rolls or striking their names off.
Answer in sentence: yes