Battle of Donatu V

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CONFLICT
Battle of Donatu V
Belligerents:	Federation vs. Klingon Empire
Date(s):	2244
Location(s):	Donatu system
Result:	Stalemate

The Battle of Donatu V, fought in 2244 in the Donatu system, was one of the few instances of open warfare between the Federation and the Klingon Empire. (TOS episode: "The Trouble with Tribbles"; TOS - Errand of Vengeance novel: Killing Blow)

Although the Federation ultimately won the engagement, both sides suffered heavy casualties. (TOS - My Brother's Keeper novel: Constitution)

Note on date: Some sources placed the Battle of Donatu V in 2242 based on an estimate that "The Trouble with Tribbles" (23 years after the battle) took place in 2265. The episode's date was later refined to 2267, but the derived date of the battle was not always updated as quickly. Above we use the corrected date of 2244.