Civil war
A civil war was a conflict internal to a culture, society, nation, or other political community.

In 2151, when Captain Jonathan Archer and T'Pol were captured by a rebellious group of Coridanites, Archer complained to her that the Vulcan database might have mentioned that the species was fighting a civil war. T'Pol countered that the database was accurate in that the Coridan government did not view the situation as a civil war. ()

The humanoid life forms of the planet Cheron destroyed their cities and killed each other off in a civil war and then made life uninhabitable to humanoid life forms, on that planet, some time prior to 2268. () 

In 2358, a civil war broke out on Parada II that lasted for the next twelve years. ()

The Mordanites of Mordan IV began a civil war that lasted forty years, due to Commander Mark Jameson supplying weapons to Karnas' rivals in 2319. ()

After the Cardassian withdrawal from Bajor in 2369, factions previously united in fighting the Cardassians resumed old conflicts. Kira Nerys believed this would lead to the fall of the Bajoran Provisional Government and a civil war, which could only be prevented by Kai Opaka. ()

Later that year a dispute between two Bajoran factions, the Paqu and Navot, could have led to a civil war but was solved by mediator Benjamin Sisko. ()

In 2370, the Cardassians, using the Kressari as cover, used the extremist group Alliance for Global Unity to try to foment a civil war on Bajor. It was Federation policy, under the Prime Directive, to not be involved in the civil war of a non-Federation culture. ()

In 2371, a dispute over soil reclamators involving Shakaar Edon again threatened to escalate into a Bajoran civil war, though the crisis was ended by Shakaar becoming first minister. ()

Benjamin Sisko believed a civil war would erupt within Starfleet and the Federation if the  destroyed the  in 2372. ()

In the late 24th century, a civil war broke out on Solum after Starfleet made first contact, with both sides fighting over whether to join the Federation. By the 25th century, the decades-long conflict had brought their civilization and species to the brink of extinction. ()

Notable civil wars 
Vulcan Civil War (4th century)
American Civil War (1860s)
Xindi Civil War (ca. 1930s to 2030s)
Second Civil War (ca. 2026)
Mordan IV civil war (2319 to 2359)
Klaestron Civil War (mid 24th century)
Parada Civil War (2358 to at least 2370)
Klingon Civil War (2367 to 2368)
Q Civil War (2373)
Great War / Kyrian-Vaskan Civil War (beginning in late 2374)
Solum Civil War (24th century to 25th century)

See also 
Conflicts

External link 
 

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 Civil war