Gong’an (公安) was a county in Jing Province on the middle Yangtze River, corresponding to modern Gong’an County under Jingzhou in Hubei. After the Battle of Red Cliffs, it served as a key base in the Sun–Liu struggle for Jing: Liu Bei held the area for a time, and later Sun Quan used Gong’an as a headquarters before moving downriver to Wuchang.
Following his surprise seizure of Jing Province in 219–220, Lü Meng was made Administrator of Nan Commandery and based in the region. Already in poor health, he died soon afterwards at Gong’an, in Sun Quan’s inner hall, at the age of about forty.