Why is Yan Zhenqing called Yan Lugong?

Because he was named the founding father of Luxian County, he was called "Yan", and because he was a secretariat of the Plain, some people also called him "Yan Pingyuan". The ancients had the habit of associating people's surnames with official positions or county records. For example, during the Three Kingdoms period, Kong Rong was the minister of Beihai, so he called it Kong Beihai.