A coup d'etat is not considered a civil war as long as there was no military conflict. A purposeful split, like what happened with the Roman Empire, also wouldn't count, and a war between those two nations later on would be a conventional war.
Similarly, a country which "formed" by rebelling from a foreign occupier, such as colonies which fought for freedom, are not considered to have had civil wars. This does not count for countries which became core territories for their occupier, such as Catalonia in Spain.
For the purposes of this quiz, countries can inherit civil wars from a parent country if it makes sense. For example, Russia is considered the same country as the Soviet Union, since it was the dominant republic of the USSR. Today's China; however, would not be considered the same as the Republic of China from the early 20th century.