500
Ways in which Han China and the Roman Empire are similar (2). And a difference (1)
What is both fall (directly or indirectly) because of the Huns, large state building projects like roads, irrigation systems, centralized government, both create a period of peace (Pax Romana and Pax Sinica), both adopt foreign religion (Christianity/Buddhism)
Difference - Use of slaves, Switch from Republic to Empire in Rome)