Title: Cong "tian xia" dao "shi jie"
Subjects: Foreign relations, History, Civilization, Foreign influences, East and West, Diplomatic relations, Han Dynasty (China), Tang Dynasty (China)
Places: China
Time periods: To 1644, Han dynasty, 202 B.C.-220 A.D., Tang dynasty, 618-907, 221 B.C.-960 A.D.