I think your answer would be, The belief that slaves were personal property and not people (I'm not 100% sure) hope this helps
~ Natalia
If the movie is perhaps a documentary, then it is telling you factual information of actual events (includes pictures or pictures of actual documents or events); this makes it a primary source.
If the movie is based off of real events, has factual information, but also has added information to create a well-rounded plot, this makes it a secondary source.
Japan needed abundant natural resources to support both its population and its empire, something that the country lacked.
Answer:
Rome was able to gain its empire by extending some form of citizenship to many of the people it conquered. Military expansion drove economic development, bringing enslaved people and loot back to Rome.
