Which country is Warren from in the Romance of the Three Kingdoms?

Hua Tuo, a character, was born in Peiguoqiao (now Bozhou City, Anhui Province). According to textual research, he was born in the first year of Yongjia in Han Dynasty (AD 145) and died in the 13th year of Jian 'an (AD 208). Famous medical scientists in the three kingdoms. When I was young, I studied abroad, but I didn't want to make progress in studying medicine. I practiced medicine all over Anhui, Shandong, Henan and Jiangsu. Hua tuo has been practicing medicine all over the world all his life, with a good reputation and many achievements in medicine. He is proficient in internal medicine, surgery, gynecology, pediatrics and acupuncture, especially in surgery. Later, he was killed because he refused to accept Cao Cao's call-up, and his medical books were lost. Today, there are relics such as "Huatuo Temple" in Bozhou City. Bozhou City, Anhui Province belongs to the land of Wei State.