Why do you think the Roman Empire declines after the Pax Romana?

After the murder of Julius Caesar, a period of civil war erupted in Rome.

Explanation:

Octavian defeated Lepidus in battle, and then turned his armies against the more powerful Mark Antony. Antony had fallen in love with and married the spellbinding queen of Egypt, Cleopatra. At the Battle of Actium off the coast of Greece in 31 B.C.E., Octavian's navy defeated the navy of Antony and Cleopatra, who later both died.

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a. competition with other nations.

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