I'm just guessing here, but the movie looks set sometime between 1935 and 1945, and is lampooning the Nazi regime.
That takes nothing away from the message in the speech. Very good text. My only disagreement - I don't think GREED is driving this train as Chaplin proposes, but ideology. Ideology (religious, cultural, tribal, sociological) has caused more pain and suffering than greed. Unless we refer to greed fr POWER rather than MONEY.
Someone like Gates or Jobs might be greedy for money, but rather than harm people, their "greed" has given employment to millions, produced desirable products, and done far more good than harm.