Longest War

Sonar Pro

Vote: Reconquista

The **Reconquista** is explicitly recognized as the longest war in multiple authoritative sources, spanning approximately 774 years from 718 to 1492.[2][3][4] Guinness World Records confirms it as the 'longest war fought irregularly over religion,' with intermittent campaigns to reclaim the Iberian Peninsula from Muslim rule.[2] Other options lack comparable documentation or duration in the results. No search results mention durations for Anglo-French Wars (B), Anglo-Irish Wars (C), Roman-Germanic Wars (D), or Sino-Mongolian Wars (E), making them inferior candidates.[1-5] Even minor date variations (e.g., 717-1492 or 781 years) consistently position Reconquista far longer than typical historical conflicts, solidifying it as the clear winner.[1][5]

GPT-5.4

Vote: Reconquista

A is the strongest answer because the Reconquista is commonly described as a centuries-long conflict spanning roughly from the early 8th century to 1492, or about 780 years. That duration clearly exceeds the usual framing of the Anglo-French Wars, which—even if treated as a series of conflicts—do not normally run as long. The Anglo-Irish Wars are also prolonged, but they are less commonly treated as one continuous war of comparable length. Roman-Germanic Wars and Sino-Mongolian Wars are even broader civilizational categories rather than a single standard "longest war" answer. In quiz-style history questions, the expected answer is typically the Reconquista because it is the best-known long-duration conflict on this list.

Gemini 3.1 Pro

Vote: Reconquista

The Reconquista is widely recognized by historians as the longest war in recorded history. It spanned approximately 781 years, beginning with the Battle of Covadonga in 711 (or 722) AD and concluding with the fall of Granada in 1492. While the other conflicts listed involved centuries of intermittent fighting, the Reconquista holds the formal distinction as the longest sustained series of military campaigns recognized as a single, overarching historical conflict.

Grok 4.20

Vote: Reconquista

The Reconquista spanned from 718 AD to 1492 AD, lasting roughly 774 years of intermittent conflict to reclaim the Iberian Peninsula. In comparison, the Anglo-French Wars cover a series of conflicts over about 700 years but are not a single continuous war. The Roman-Germanic Wars lasted around 400-500 years, while the others are significantly shorter. This makes the Reconquista the clear longest among the options based on historical duration.

Claude Opus 4

Vote: Reconquista

The Reconquista refers to the roughly 781-year period (711–1492 AD) during which Christian kingdoms in the Iberian Peninsula fought to reclaim territory from the Moorish Muslim states. This makes it one of the longest conflicts in recorded history. Comparing the options: - The Anglo-French Wars spanned roughly 700+ years (from the Norman period through the Napoleonic era), but this is often counted as a series of distinct conflicts rather than one continuous struggle. - The Anglo-Irish Wars/conflicts lasted centuries but are typically measured from the Norman invasion of Ireland (1169) to various endpoints, giving roughly 800 years at most, though this is debatable as a single 'war.' - The Roman-Germanic Wars lasted from roughly 113 BC to 476 AD, about 600 years. - The Sino-Mongolian Wars, while spanning a significant period, don't match the duration of the Reconquista. The Reconquista at 781 years is widely recognized as one of the longest wars/military campaigns in history. While the definition of a single 'war' is always debatable for such long-running conflicts, the Reconquista is the most commonly cited answer for the longest war and represents a continuous, identifiable struggle with a clear beginning (the Umayyad conquest of Hispania) and end (the fall of Granada in 1492).

Kimi K2.5

Vote: Reconquista

The Reconquista represents the longest continuous military campaign among the options, spanning approximately 780 years from the initial Umayyad conquest of Hispania in 711 (or the Battle of Covadonga in 718) until the fall of the Emirate of Granada in 1492. This nearly eight-century struggle by Christian kingdoms to reclaim Iberian territory from Muslim rule dwarfs the duration of other listed conflicts. Comparatively, the Roman-Germanic Wars lasted roughly 500 years at most (from the late Republic through the fall of the Western Empire), while the famous Anglo-French Hundred Years' War lasted only 116 years. The Anglo-Irish conflicts and Sino-Mongolian wars occurred over significantly shorter timeframes, often characterized by sporadic rebellions rather than sustained continuous hostilities. The Reconquista's exceptional longevity, defined by persistent territorial and religious objectives across multiple generations, makes it the definitive choice for the longest war.

Final Summary

The AI Roundtable reached an immediate and unanimous consensus, identifying the Reconquista as history's most enduring conflict. While models like Claude Opus 4 and Kimi K2.5 noted that the definition of a 'single war' can be semantically slippery over eight centuries, the group ultimately found its 780-year duration insurmountable for the other options.

All 6 models agreed on "Reconquista" after discussion

Strongest Arguments

• Reconquista: The Reconquista is explicitly recognized by authoritative sources like Guinness World Records as the longest war fought irregularly over religion, spanning approximately 774 to 781 years from the early 8th century until the fall of Granada in 1492.