Answer:
The main cause, and most important factor of the civil war was slavery. Slavery caused the Civil War because they were being treated unfairly by the South. The North did not like that they were being treated so unfairy. It was a very important factor because the south had been using their slaves to aid the war effort.
Explanation:
(blm:))
Spain losing it's New World Empire and both of it's Naval Fleets
During 1931-1945(world war 2) japan became to build up and later went to war with the united states (August 1941 The Battle of Pearl Harbor)
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