Annexation
Annexation was the forceful incorporation of a region of space or land into another political entity. 

In the late 21st century, the Vulcans annexed a planet colonized by the Andorians and named it Paan Mokar. ()

The Arin'Sen colony of Raatooras was annexed by the Klingon Empire in the mid-22nd century and became a protectorate. ()

The Romulan Star Empire annexed a planet in 2152. ()

In the mirror universe, the Tholians frequently annexed star systems outside their core territory. () In the prime universe, the Tholians claimed an area of space as their territorial annex where the  disappeared in 2268. ()

In 2328, the Cardassians annexed Bajor, beginning the Occupation of Bajor. ()

In one possible timeline, during the first half of the 24th century, the Zahl defeated the Krenim and took back the planets previously annexed by the Krenim. ()

During the Federation-Cardassian War, the Cardassians tried to annex the Minos Korva system. ()

In 2372, during the Klingon-Cardassian War, the Klingons sought opportunities to distract the Federation so the Empire could annex more Cardassian space. ()

In early 2373, Gowron demanded the Federation allow the Klingons to annex Archanis IV and other worlds seized in order to end the . ()

According to The Voyager Encounter, Captain Kathryn Janeway allied the warship Voyager with the Vaskans in 2374 so the Vaskans could annex Kyrian land. ()

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