Alpha Quadrant Alliance (United Federation of Planets, Klingon Empire, Romulan Star Empire) vs. Dominion, Cardassian Union, Breen Confederacy   Alpha Quadrant Alliance (United Federation of Planets, Klingon Empire, Romulan Star Empire) Casualties: Unknown, Tenth Fleet out of position during initial attack. Betazed conquered in ten hours.

Dominion, Cardassian Union, Breen Confederacy Casualties: Unknown, presumably few.

Result:
Decisive Dominion victory.
 


Dominion forces cross the border to attack Federation space.



Betazed, from orbit

 

The Battle of Betazed was a surprise Dominion offensive against the Federation member world of Betazed during the Dominion War in 2374.

The Jem'Hadar had secretly assembled a large invasion force in the Kalandra sector, which Starfleet had believed was too far from Dominion territory to represent a major threat. At the same time, the Tenth Fleet was caught out of position at the start of the invasion during a training exercise. The disadvantage was compounded by the relative weakness of Betazed's antiquated defenses.

Ultimately, the Dominion conquered the planet and its outlying colonies in only ten hours - a humiliating defeat for the Federation.

Several weeks later, the Dominion attempted to form a supply line running from Betazed to the Argolis Cluster, hoping to eventually launch an attack on Vulcan.

Later that year, the Second Fleet launched at least three attacks against the Dominion positions on the planet, but the continual Dominion reinforcements and the fortification of the planet stopped them from succeeding.