How historians name real wars
Real war names are almost never invented by participants: historiography assigns them decades later. The Thirty Years' War got that name when it had ended and could be told. World War I was simply the Great War until the second one broke out. This is relevant for worldbuilding: your world's internal chronicler names conflicts retrospectively.
There are three dominant logics in real names. By duration: Hundred Years, Thirty Years, Seven Years. By opposing parties: Anglo-Zulu War, Greco-Persian War, Pacific War. By cause or motive: War of Spanish Succession, War of Independence, Carlist Wars. If your world has chroniclers, use these logics to feel authentic.
Some wars adopt names of decisive battle or emblematic place: Vietnam War, Falklands War. This works if your narrative had an iconic event synthesizing it. The Five-Day War in South Sudan (2016) was named for the exact peak duration. Quantitative precision lends historical credibility.
Patterns for fantasy worldbuilding
In epic fantasy, wars usually have more poetic names than real ones, but the best fantasy respects underlying historiographical logic. Tolkien's Wars of the Ring follows classic pattern: name of causal object + conflict type. Martin's Dance of the Dragons names the conflict by its protagonists (Targaryens rode dragons).
For multiple conflicts in the same world, maintain typological coherence. If you have War of the Five Kings, you can also have War of the Three Princes and Schism of the Seven Houses: the numerical pattern repeats and creates recognition. If you mix War of the Kings with The Black Awakening and Operation Crucible in the same world, it sounds inconsistent.
Ancient conflicts in your lore should have simpler, mythified names; recent ones more prosaic and specific. A 3000-year-old war in your world will be called The Bloody War or The Schism; one from 30 years ago will be The Targaryen War of Succession or The Northern Rebellion. This temporal gradation in name complexity creates a sense of historical depth.
Mistakes that break historical immersion
Names too modern for pre-industrial contexts: Operation Crucible, Mission Steel or Protocol Sigma sound like 20th-century Pentagon. If your fantasy is medieval, those names break tone. Reserve modern military language for sci-fi or contemporary thriller.
Acronyms in fantasy: WAR-7 or OMEGA War rarely work in pre-printing worlds. Acronyms require massive written culture and administrative bureaucracy. In oral or limitedly literate societies, wars are named with descriptive phrases.
Names that spoil too much: The War That Ended Everything or The Final Conflict of the World are hyperbolic and predict the outcome. Better ambiguous names where the reader discovers how grave it was as the story progresses. The War of the Ten Days sounds brief until it's revealed it killed 80% of the population.
Repeating real cultural references in fantasy without transformation: if your fictional war is called The Vietnam War of Akkad or The Elven Hiroshima, you lose immersion. Obvious analogies work in satire or intentional allegory, not immersive worldbuilding.
How to build credible conflicts, not just names
The name is the iceberg's tip. For a fictional war to be memorable, you need to define five layers: cause (succession, religion, resources, border), sides (at least two, ideally both with reasonable motivations), duration (days, years, decades), outcome (absolute victory, negotiated peace, mutual exhaustion) and consequences (long-term political, social, economic changes).
The best fictional conflicts have moral complexity. If your war is 'good kingdom vs evil kingdom', it's manichean and boring. If both sides have legitimate reasons and committed atrocities, the war becomes rich narrative material. The historical Wars of the Roses works in fiction precisely because no side is clearly right.
Document three key battles or events of your invented war: one at start, one in middle (turning point), one at end. You don't need detailed scenes, just name, location and outcome. This documentation creates depth even if you only mention events in passing in your main narrative.
Think about cultural memory the war left. What songs are sung about it? What monuments exist? What language insults derived from it? 'More cowardly than a Lannister at Riverrun' is a credible insult evoking a specific event. These living details separate professional worldbuilding from mere nomenclature.