Short answer: Only a handful of great commanders have a research-based IQ estimate, and the core figures come from Catharine Cox's 1926 study of people born between 1450 and 1850. Napoleon ranks first at 135 for childhood and 140 for early adulthood. George Washington follows at 125 and 135, then Ulysses S. Grant at 110 and 125. Alexander, Hannibal, Caesar, Suleiman and Churchill have no published estimate. In Cox's data, military leaders scored lowest of any field.
At a glance
| Top verified estimate | Napoleon: 135 (childhood), 140 (ages 17–26) |
|---|---|
| Main source | Catharine Cox, The Early Mental Traits of Three Hundred Geniuses (Stanford, 1926) |
| Sample window | People born 1450–1850 with achieved, not inherited, eminence |
| Commanders with no estimate | Alexander, Hannibal, Caesar, Suleiman, Churchill, Genghis Khan, Sun Tzu |
| Field ranking in Cox | Military leaders scored lowest of her domains |
| Measured scores | None on record for any commander listed |
The Ranking
The table ranks commanders only where a published, research-based estimate exists. Everyone else is listed as "No scholarly estimate," in order of appearance rather than merit. We do not fill gaps with invented numbers.
| Name | Estimate | Basis |
|---|---|---|
| Napoleon Bonaparte | A1 135, A2 140; 145 corrected | Cox (1926), rated from school records and early career |
| George Washington | A1 125, A2 135; 130 and 140 corrected | Cox (1926), reprinted in Simonton (2006) |
| Ulysses S. Grant | A1 110, A2 125; 115 and 130 corrected | Cox (1926), reprinted in Simonton (2006) |
| Alexander the Great | No scholarly estimate | Born 356 BC, outside Cox's 1450–1850 sample |
| Hannibal Barca | No scholarly estimate | Born 247 BC, outside Cox's sample |
| Julius Caesar | No scholarly estimate | Born 100 BC, outside Cox's sample |
| Suleiman the Magnificent | No scholarly estimate | Hereditary ruler; Cox excluded inherited rank |
| Winston Churchill | No scholarly estimate | Born 1874, after Cox's 1850 cutoff |
| Genghis Khan | No scholarly estimate | Lived before 1450, outside Cox's sample |
| Sun Tzu | No scholarly estimate | Ancient; outside Cox's sample |
Three names carry numbers. All three were born inside Cox's window and rose by achievement. The ancients, the hereditary rulers and the moderns fall outside her rules, so they have none. Each linked page explains the evidence for that commander in full.
Why a 1926 Study Still Supplies the Numbers
Nobody took a modern IQ test before 1905. Every figure for a historical commander is therefore a retrospective estimate, and the only systematic set was built by Catharine Cox for Lewis Terman's Genetic Studies of Genius. She studied 301 eminent people drawn from a ranked list of the 1,000 most eminent figures in history.
Her rules were strict. Subjects had to be born between 1450 and 1850, so that enough childhood records survived. Their distinction had to be achieved rather than inherited, which removed kings and sultans. Three raters, Cox, Terman and Maud Merrill, turned each subject's documented development into an IQ for two periods: birth to 17 (A1) and 17 to 26 (A2). Cox then computed corrected figures to offset the pull of thin records toward the average.
In 2006 the psychologist Dean Keith Simonton reused her figures for the eight presidents in her sample, including Washington and Grant, in the journal Political Psychology. For the other presidents he imputed estimates statistically from personality ratings, a looser method. For the full background, read historical IQ estimates explained and IQ of famous historical figures.
Soldiers Scored Lowest
Cox compared her fields of achievement. In Simonton's 2020 summary of her findings, military leaders scored the lowest. Philosophers, writers and scientists ranked higher. Her single case in the top childhood band, 190 to 200, was the philosopher John Stuart Mill.
That result does not prove generals are less intelligent. It most likely reflects the method. Cox rated documented precocity: early reading, early writing, early intellectual work. Future philosophers and poets leave paper trails as children. Future soldiers, whose eminence comes from action, leave fewer. Union general William Tecumseh Sherman, for example, appears among her cases rated 120 to 130 for childhood. The Spanish conqueror Hernán Cortés is in the sample too. Low evidence yields a low estimate, which is why Cox added reliability corrections in the first place.
The Three Commanders With Numbers
Napoleon. At Brienne his teachers rated his mathematics and history excellent, his French and Latin middling. He finished the École Militaire in 1785 ranked 42nd of 58. Cox's 135 and 140 reflect that mixed record. His adult output, from the 1804 Civil Code to Austerlitz, argues for more range than any score shows. Full profile: Napoleon's IQ.
George Washington. Schooled in practical mathematics, he became surveyor of Culpeper County at 17 and never attended college. Jefferson wrote in 1814 that Washington's mind was "great and powerful, without being of the very first order." Cox's 125 and 135 match that verdict. Full profile: George Washington's IQ.
Ulysses S. Grant. The Union's winning general and 18th president has the lowest figures of the Cox-rated presidents: 110 for childhood and 125 for early adulthood, or 115 and 130 corrected. He still led the Union armies to victory in the Civil War. See our Grant profile.
Great Commanders Without a Number
Several of history's most famous commanders have no scholarly IQ estimate at all. Their evidence is their record.
- Alexander the Great studied under Aristotle from about 13 to 16 and never lost a pitched battle.
- Hannibal surrounded and destroyed a far larger Roman army at Cannae on 2 August 216 BC.
- Julius Caesar wrote the Gallic War commentaries and introduced the 365-day Julian calendar in 45 BC.
- Suleiman the Magnificent consolidated Ottoman law into one code and wrote poetry as Muhibbi.
- Winston Churchill won the 1953 Nobel Prize in Literature "for his mastery of historical and biographical description as well as for brilliant oratory in defending exalted human values."
Online IQ figures for these five come without a named researcher or method. For broader context on leadership, see the greatest leaders in history.
What Command Actually Demands
The strongest cognitive evidence for great generals lies in specific feats. At Cannae, Hannibal coordinated a withdrawing center, closing flanks and cavalry in the rear across an entire battlefield. At Alesia in 52 BC, Caesar built an inner siege line of about 16 kilometers and an outer line of about 20.7 kilometers, and held both. Pliny the Elder reported that Caesar could dictate four letters at once.
Yet the same careers show where intelligence runs out. Hannibal won the battles and lost the war at Zama in 202 BC. Napoleon invaded Russia in 1812. Caesar misread the senators who killed him. Command rewards reasoning, but it also demands judgment, nerve, luck and political sense, none of which an IQ number measures. Hannibal himself, according to Appian, ranked Alexander first among generals, Pyrrhus second and himself third, a judgment of results, not test scores.
Head-to-Head Comparisons
For side-by-side careers, use our comparison pages:
- Napoleon vs. Alexander the Great
- Napoleon vs. Julius Caesar
- Alexander the Great vs. Julius Caesar
- Napoleon vs. Wellington
- Winston Churchill vs. Napoleon
- George Washington vs. Abraham Lincoln
How to Read These Numbers
Cox's raters worked with the Stanford revision of the Binet-Simon scale, the test of their day. Modern tests such as the Wechsler scales use deviation IQ, with a mean of 100 and a standard deviation of 15. The two are close but not identical, so treat old figures as approximate. On a modern scale, 135 is roughly the top 1 percent; see IQ 135, IQ 140 and IQ 125.
Error bands matter. A single modern test score carries a confidence interval of about 5 points either way. Historical estimates are far looser: for the presidents Cox rated, her reliability corrections moved figures by 5 to 30 points. If you want a number of your own, our free IQ test is a practice screener, not a clinical assessment.
Frequently asked questions
Which military leader had the highest IQ?
Among commanders with a research-based estimate, Napoleon ranks highest: Catharine Cox's 1926 study gave him 135 for childhood and 140 for early adulthood, and 145 after correction. Alexander, Hannibal and Caesar cannot be ranked against him, because no scholarly estimate exists for any of them.
What was Napoleon's IQ?
Napoleon never took a test. Cox estimated 135 for his childhood and 140 for ages 17 to 26, based on school records and early career; secondary tabulations of her corrected data list 145. Online claims of 160 or 180 have no source. Details on our Napoleon IQ page.
Did Alexander the Great have a high IQ?
The record suggests so, but no number can show it. Alexander died in 323 BC and falls outside every systematic study of historical IQ. The evidence is indirect: an education under Aristotle, a habit of reading even on campaign and an unbeaten record in pitched battle. See Alexander the Great's IQ.
Why did soldiers score lowest in Cox's study?
Largely because of the method. Cox rated documented precocity in childhood and youth, such as early reading and writing. Future writers and philosophers leave more of that record than future generals, whose eminence comes from later action. Thin records push estimates toward the average, which is why she also published corrected figures.
Is there an IQ estimate for Winston Churchill?
No scholarly estimate exists. Churchill was born in 1874, after the 1850 cutoff of Cox's study, and no later researcher has published a figure. His documented record includes the 1953 Nobel Prize in Literature. See Winston Churchill's IQ.
Sources
- Catharine Cox, The Early Mental Traits of Three Hundred Geniuses (1926), full text — Case lists by IQ band: Napoleon, Washington, Sherman, Mill; Cortés in the appendix
- Simonton, Galton, Terman, Cox (Gifted Child Quarterly, 2020) — Cox's sample rules and raters; military leaders scored lowest
- Simonton (2006), Presidential IQ, Openness, Intellectual Brilliance, and Leadership (PDF) — Cox figures for Washington and Grant; imputation for other presidents
- Riot IQ: What Was Napoleon's IQ? — Cox's A1 135 and A2 140 for Napoleon
- Nobel Prize: Winston Churchill, facts — Birth 1874; 1953 prize motivation
- Wikipedia: Battle of Cannae — Date and tactics of Hannibal's double envelopment
- Wikipedia: Battle of Alesia — Lengths of Caesar's fortification lines
- Wikipedia: Hannibal — Appian's account of Hannibal's ranking of generals
Editorial standard: IQ figures for historical figures are retrospective estimates and are labeled as such; scores for living people appear only when the person disclosed them or a reputable outlet reported them. Corrections: contact the editors.
