How dangerous was the Mexican-American War for American soldiers?

The Mexican War of 1846-1848, largely forgotten today, was the second costliest war in American history in terms of the p ercentage of soldiers who died.  Of the 78, 718 American soldiers who served, 13, 283 died, constituting a casualty rate of 16.87 percent.  By comparison, the casualty rate was 2.5 percent in World War I and World War II, 0.1 percent in Korea and Vietnam [TC: you’ll find better but still lower estimates here], and 21 percent for the Civil War.

That is from American Ulysses: A Life of Ulysses S. Grant, by Ronald C. White, a good book by the way.  I had not known that a possible U.S. takeover of “Santo Domingo” (today’s D.R.) was such a big issue during Grant’s administration.


It was the worst war we fought, from a moral position. Many have described it as a result of the Texas Mexico war, but it seems indefensible morally. Melliville was against it in Moby Dick.

What did we gain by it? The lands where bitter Steve Sailer types exists?

What if we hadn't fought that war? Wouldn't we be better off? California is worse off being part of the Unites States. Had it been part of Mexico, it could have negotiated much better terms.

"California is worse off being part of the Unites States"

That's quite a claim you're making there, amigo.

That gave me pause as well. A more interesting thought experiment would be to posit that California might have been better off being its own country....

Well, I think the optimal decision for California was integrating in the US because when progress came (railroad, gold rush, technology, orchards, OIL!) it was built with East Coast capital and under the US business friendly legal framework...

that's my take the various counterfactuals are pretty cool to play with. :-) :-)

Oh no doubt! I can't recall it's name but there was a historical fiction novel back in the 60s or 70s about a universe in which Cali w/ the Southwest (The Greater Republic of California), and Texas ended up as independent states and form an alliance fighting a war with the USA with international recognition (and support) from the USSR.

Bears & Armadillos....WOLVERINES!!!!!

Lincoln was against it too.

"Is it a misfortune that magnificent California was seized from the lazy Mexicans who did not know what to do with it?”
- Karl Marx

“In America we have witnessed the conquest of Mexico and have rejoiced at it. It is to the interest of its own development that Mexico will be placed under the tutelage of the United States.”
- Friedrich Engels

Even the left wing of the time thought Mexico, a backwater semi-feudalist military dictatorship, was not the right country to control California.

Heck, even before the Bear Flag Revolt, various Californio factions talked about secession and annexation by various other powers. Pio Pico lobbied for joining the UK. Mexico really, really ignored Alta California and were happy to let Americans in illegally to settle.

Not only that, but Russia had established multiple settlements, including Fort Ross, in Northern California. Mexico had done nothing about it for three decades: the multiple Mexican governments, who invariably overthrew each other in semi-violent revolutions or thinly-veiled coups (Santa Anna's return to power following the Pastry War with France) in severe conflicts over liberalism/traditonalism and federalism/centralization, barely controlled Mexico itself beyond what would later be called the Distrito Federal and were constantly suppressing revolts throughout present-day Mexico both in the North (Sonora, Zacatecas, Rio Grande, and of course Texas) and South (Yucatan and Tabasco) while very early on losing control of Nicaragua, Guatemala, Honduras, and El Salvador.

Goos point, Anonymous. It is interesting to remind that Marx and Engels were not all on a "Leninist position" concerning wars -- they would not oppose the most advanced country as "imperialist", they would support it. Lenin made an important change to this politics that has influenced the whole left, to this day and well beyond the communist parties.

Another example of Marx's position, surprising from a Lenisist/modern leftist point of view, is that he was enthusiastically for France end UK against Russia during the Crimean war in 1852. Indeed, France and UK were much more advanced politically and economically than Russia (which still had serfdom).

In many things a cure of real marxism would make the modern left much less unbearable.

The war with Mexico was very controversial in its day, but not necessarily for the reasons that contemporary Americans would think: taking land from Mexico.

It was controversial at the time because Northerners saw it as an attempt by Southern slave owners to expand the territory open to slavery. And not because slavery is itself immoral, but mostly because Northerners already were concerned with the fact that the slave states' political power far exceeded what their number of white citizens would indicate they should have. There was an expectation at the time that slave state political power would naturally wane as the country expanded westward, but the annexation of Mexican territory, where slavery was also legal, threatened that future of national political power shifting to the non-slave states.

Slavery was not legal in Mexico, although Texas had a "bye" until 1830. At the time of the Texan Revolution (1835) slavery was illegal in all of Mexico. Some Texan slaves fought on the Mexican side during the Texan Revolution for that reason.

Brett is right, the US north thought the US south would extend slavery into Mexico (and all of Latin America and even South America) if given the chance, despite slavery being nominally illegal there.

Bonus trivia: the USA as in United States of Americas (plural) would have been very cool! Keep in mind slavery would have eventually died out, like it did in Brazil late in the 19th century without a civil war, eventually.

Don't downplay the value of Los Angeles, San Fran, San Diego, etc. Without California, the american film industry probably winds up in, say... St. Louis and it's just demoralizing to everyone involved.

California has been a massive net contributor to the federal treasury for pretty much its entire existence as a state.

I would say that the worst war fought by the Americans, from a moral point of view, was the war against Philippine (1899-1902).

Korea amd Vietnam killed about 95,000 US soldiers combined. A death rate of 0.1% implies that 95 million US soldiers served. So much for numeracy.

Agreed. Death rates seem wrong.

If my memory serves, WWII was about ~50 deaths per 1,000 combatant years for US troops. Vietnam was ~20. Recent ops runs at ~5.

I don't know where you're getting that figure from, but I believe you are off by about 40,000.

Sorry, misread your comment. You said combined. Even then, running the numbers Vietnam was .01-.02. But that is because the official numbers run from 1960-75.


I think you're misreading still. Professional military analysts use deaths per combatant-year for gauging lethality across wars. Amateurs, newspaper editors, and commentators use total deaths or deaths per combatant, which is far less informative because it doesn't meaningfully split long and short war durations or combatant service terms. In broader terms, deaths per population-year is also sometimes useful.

Figures are ex-Dunnigan et al.

Those numbers seem way off.

The actual numbers for Vietnam, seem to be 58K out of 2.7 million Americans who served in Vietnam. That would be over 2%.

Also most military books define casualties as wounded plus killed, not just killed as TC does.

We'd better build that wall then. Keep out those bloodthirsty murderers and rapists. They can eat their tacos and burritos on the other side of the Rio Grande. #RememberMollie

Report to the re-education camp, comrade.

Tacos are part of San Diego culture part of the USofA, Mexicans are stealing them.

Yeah, right, and pizzas were created in Chicago and not in Naples... :-) :-)

Pretty much correct, actually

'had not known that a possible U.S. takeover of' fill in the blank using a Central American/Caribbean nation 'was such a big issue during' fill in the blank 'adminstration.' Just in my lifetime, recognizing that 'take over' needs to be replaced by the appropriate Cold War euphemism regarding the actions taken in Latin America, we would have Cuba/Kennedy, Dominican Republic/Johnson, Nixon/an extensive list, Ford gets a bit of a pass as his administration seems to have merely kept Nixon's goals in place, the Carter administration failed miserably in this regard, but then a new morning dawned under the Reagan/Bush administration. Admittedly, after losing our best modern excuse to do whatever we wanted to do what we wanted in 'our' backyard, things have been a bit more quiet. Most Latin American countries seem to be following the American playbook closely enough that they do not need any help from the shining city on the hill to stay on the proper path.

Or just ask anyone from Latin America - they actually seem to know more American history in this regard than even widely read Americans.

"Or just ask anyone from Latin America - they actually seem to know more American history in this regard than even widely read Americans."

Of course, our interventions are gnat size to us, giants to the small countries affected.

Death rates on early voyages of exploration tended to be astronomical. For example, only about 7% of Magellan's crew made it around the world.

Interesting that people would voluntarily sign on to these voyages. People must have been much less risk averse than they are today.

During the Rural Electrification efforts in America, electrical linemen had a 50% death rate.

The poor, desperate and adventurous have always undertaken dangerous jobs, often at low pay. But low pay is high relative to no pay.

I can only guess that the rewards offered to these explorers were substantial, albeit speculative.

Melville's Ishmael gleefully sought out a highly dangerous profession merely for psychic benefits. While fictional, I dont doubt there are many real people like him.

They may not have known quite how risky it was?

I mean, such voyages may have had an average 10% death rate, but some missions are 100%….

Also, we have to account for the death rate for a poor person in that era if they just stayed home for 3 years. It would presumably be >0%.

People of that era had very few ways of accurately assessing risk. They couldn‘t pick up a newspaper and find any statistics that would tell them how dangerous a trip a trip around the world was likely to be. Since death by disease and war was not uncomfortable uncommon on land, sailing was probably perceived as worth the risk, and since everyone was likely to know or have heard about someone else who had done well off a recent sailing voyage, survivor‘s bias probably skewed people‘s perception of risk as well.

Not always voluntary - you had crimps and press gangs to ensure a ship had a full crew of non-officers

Wikipedia states US military casualties as 1,733 killed in battle, citing Clodfelter, M. (2017), Warfare and Armed Conflicts: A Statistical Encyclopedia of Casualty and Other Figures, 1492–2015 (4th ed.) at 249:

I haven't checked the source document. That said, I am surprised that the estimate in Clodfelter and the estimate in the book Tyler referred to can differ by an order of magnitude.

Hi Art, hope your import export business is thriving.

I was responsible for the order of magnitude difference.

You're welcome Mexico.

+1, excellent post

". Of the 79,000 American troops who took part, 13,200 died for a mortality rate of nearly 17 percent—higher than World War I and Word War II. The vast majority were victims of diseases such as dysentery, yellow fever, malaria and smallpox. According to scholar V.J. Cirillo, a higher percentage of U.S. troops died from sickness during the Mexican invasion than any war in American history. "

Interesting, as usual. Of all the things to focus on from a Grant biography, Cowen picks this. Here's a good primer on the Mexican-American War, from RealClearHistory.

The better metric is either deaths per soldier-year or deaths per population-year.

I note that Texan and American casualties are being conflated here; I also wonder if all irregulars are properly counted...

Correct, but then the numbers would be extremely low and therefore incredible to a casual observer.

The vast majority of troops in any war are combat support and combat service support. Many soldiers on active duty don't even make it into the theater of war. This has the potential of deflating the metrics and misrepresenting actual danger. I'm not sure I have a complete solution to this conundrum, especially since ideal data has not been collected for every war. But your approach is a good start and better than alternatives.

The result is that all of the recent wars in the GWOT have the lowest casualty rates of any wars in history. Aside from raw military superiority, the US made a conscious choice for a high Capital to Labor ratio in the military. We let expensive machines do the killing and dying instead of soldiers. This hasnt helped our military budget, but I find the cost-benefit tradeoff worthwhile.

"Of the 78, 718 American soldiers who served, 13, 283 died, constituting a casualty rate of 16.87 percent". Do Americans really use "casualty" to refer only to the dead? In that case how do you refer to the wounded?

No. Casualty properly includes the wounded (and ill).

In the recent era of anti-war sentiment, the word "casualty" has become a casualty of propaganda battles.

In this instance the sentence clearly discusses a death rate, so I dont fault the author for imprecision.

I do. He should have used "death rate."

Medical reports use "morbidity" for ill or injured, and "mortality" for the dead.

Tyler quoted a paragraph from page 96 . google books offer this page as preview ( ). Please read the last 3 sentences Tyler did NOT quote:

"The Mexican War of 1846-1848, largely forgotten today, was the second costliest war in American history in terms of the percentage of soldiers who died. Of the 78, 718 American soldiers who served, 13, 283 died, constituting a casualty rate of 16.87 percent. By comparison, the casualty rate was 2.5 percent in World War I and World War II, 0.1 percent in Korea and Vietnam, and 21 percent for the Civil War. Of the casualties, 11,562 died of illness, disease, and accidents. Thirty-nine men Grant had known at West Point died. Four members of his 1843 class lost their lives."

Between the Mexican-American war and WW1 Joseph Lister came up with the idea of antiseptic surgery on 1867 and the practice became widespread by 1890. Penicillin was tested during WW2 further reducing infection + gangrene deaths.

It makes no sense to compare casualty rate from 1848 (killed in action + disease) to casualty rate from 1970 which is mostly comprised by killed in action. Death by infection was not caused by the war, life was just like that at the time.

The right comparison would be killed in action VS killed in action. For the Mexican-American war : (13283 death - 11562 disease) / 78718 serving = 0.0218 or 2.2%.

Modern medical practices and rapid evacuation of wounded has also increased battlefield survivor rates. Soldiers who would have died in prior wars now survive.

Body armor, specifically SAPI plates makes it impossible to compare. Soldiers literally get shot and return to duty same day.

Medevac helos transporting wounded within an hour.

A total transformation in the use of tourniquets. Now that there’s no risk to limb loss it’s step one of any GSW limb injury or major shrapnel wound.

Sure can probably comment on this as well in better depth from the doc perspective.

Including or excluding death due to infection or level of medical science in general seems to depend on just what point one wants to make. If the point is the total cost of a war in human lives of participants does it matter? To exclude death due to infection would imply those people would likely have died from the same infection without the war having occurred. That seems questionable.

However, if you want to talk about just the man-kills-man directly aspect of war, perhaps excluding it makes some sense.

A 10% death rate by infection was much higher than the civilian rate at the time. Being crowded into camps were sanitation was not always maintained, drinking water from dubious sources while on the march, etc caused many deaths thus count as death caused by the military action if not in battle.

Maybe if Americans did not seek territorial aggrandizement and enaving other peoples, fewer Americans would have died. In Texas, in NYC, in Washington, in Vietnan.

Brazil can return to Paraguay the territory won over the Paraguayan war.

So, both Mexico and Paraguay lost 40% of territory to a people seeking territorial aggrandizement.

Not true at all! Brasil fought a war for survival after an unprovoked and dastardly surprise attack when Paraguay tried to annex Brazil.

Brazil's Emperor Pedro II (called "Marcus Aurelius' grandson" by the people) refused to conquer Paraguai (which das bitterly criticized by Brazilian president Quadros) and granted protection to Paraguay against Argentinas intentions of conquest. Brasil is the only reason an independent Paraguay existe at all. Brasil also generously forgave Paraguay's war reparations and decided to buy the country's surplus energy.

Of course, the war with Mexico was the training ground for our civil war; and the victory against Mexico would foretell the cataclysm to come. The treaty that ended the war with Mexico was a bonanza for the U.S., expanding the U.S. territory by about a quarter: Texas, New Mexico, California (including the current states of California, Nevada, and Utah, most of Arizona and New Mexico, and part of Colorado). For it, the U.S. paid Mexico the sum of $15 million, relinquished claims to Baja California, and assumed $3.5 million in Mexican debts. Quite a haul for such a paltry sum. What "victory" did was seal our own fate: according to Grant, our civil war was "largely the outgrowth of the Mexican War. Nations, like individuals, are punished for their transgressions". Promptly after the end of the Mexican War, Congressman Wilmot of Pennsylvania introduced legislation to outlaw slavery in the territory acquired from Mexico. Southern legislators defeated the legislation, but it put the issue of slavery squarely in front of the nation. Indeed, Lincoln, who opposed slavery and "President Polk's war", said that Polk "feels the blood of this war, like the blood of Abel, is crying to Heaven against him". Ron Chernow, Grant.

It was a pretty small force that Scott landed with and marched to Mexico City (less than 10,000 men). Santa Ana had a larger army. I'm not surprised they took high casualties (especially since they were also taking Mexico's biggest city).

The US would be so much cooler if they had taken Northern Mexico and baja CA, and Northern Mexico might not be as rough as it is today. Also Canada should be a US state, let's be real.

If you ask a Canadian they will tell you the USA already tried to make that happen and failed.

Also Canada should be a US state, let's be real.

No, Anglophone Canadians should execute a velvet divorce from Quebec and put an end to Pierre-Elliot Trudeau's tinkertoy multi-cult projects. They should also appreciate their collective accomplishments and tell their lawyers, academics, and journalists to get stuffed. Canada needs its own Trump.

They can have ours! Don't even need to send us anything in return.

I actually support Mr. Trump, but this is funny.

Boy that'd piss off those millions who moved there right after the election.

Funny how that works. Trump gets elected. Americans move to Canada and Mexicans/Central Americans move to the USA. Guess what are the net effects? Nationalist/anti-immigrants need to think real hard about whether they are actually achieving their goals. I imagine they just like the harsh rhetoric, consequences be darned.

They already had Rob Ford

Total casualties for King Phillips war was 10 x that of the Civil War. 600 to 800 out of a New England population on 52,000. By far the highest toll of any American war

I vaguely remember (from his memoirs) that Gen. Sherman missed the Mexican war on account of the slow progress of his transport ship from the east coast to California.

I wonder how comparable those ratios are. It would be good to check the ratios for support versus combat soldiers before drawing any conclusion I would think. I would postulate that over time one will find that the number of soldiers in any military that are in harms way diminishes (20 year ago I think the ratio was something like 5 non-combat support troops for each combat soldier - I don't think it was that nearly high 150+ years ago.).

I don't have any good sources or numbers handy but there's some indication (mostly focused on Vietnam) that the increasing ratio of support to combat troops means that that while casualty numbers of the overall force can go down, they may still be quite high for combat troops in general (or for specific units, but that's always been the case).

To extend this even further -- and I've seen some preliminary examinations of this for Iraq but I don't have any links -- lower casualty figures can lead to a greater exposure to combat for combat troops. Mechanism appears twofold: cost (casualties) of initiating contact is lower and so encourages both troops and officers to do so. Also, the typical surviving combat veteran sees more combat because he's less likely to have been KIA before telling you about it.

Upshot is that Iraq -- because of the low capability of the enemy, relatively small number of combat soldiers, and the extraordinary levels of protection those soldiers had -- produced a lot of troops whose ratio of days "in contact with the enemy" to "nothing happened" is extraordinarily high by historical standards, even higher than Vietnam, which in turn was higher for WW2.

If you have not seen this it is incredible (a statistical recap of WW2 casualties, compared to history as well)

0.1 percent in Korea and Vietnam [TC: you’ll find better but still lower estimates here],

Somebody misplaced a decimal point. About 3 million American soldiers were posted to VietNam at some point, of whom just shy of 2% died there. Korea was more lethal than that.

A lot of soldiers died of disease. The US had to fight the Mexicans hundreds of miles from its supply bases. Likewise, US Grant had to invade the South with extended supply lines and a thousand miles from Washington, DC. The South only fought two battles in the North. Most Union soldiers suffered severe deprivations while Southern soldiers almost always fought in friendly territory. Distance from base and environment play a part in causing casualties besides guns and cannon.

And the South still lost fair and square, as was the fate of their evil cause.

prof. t.nutjabber
you win, we surrender
porfavor call off the clergy

Chernow's book is even better.

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