By 1902, the French had spent years remodeling Hanoi, satisfied they knew tips on how to construct a greater metropolis.
Docs, engineers and colonial officers had arrived in Vietnam with grand plans. They wished to show Hanoi right into a showcase of French structure, tradition and trendy infrastructure.
They known as it their mission civilisatrice, or “civilizing mission.” The concept was that French rule would introduce the Vietnamese inhabitants to European methods of dwelling, together with trendy sanitation.
No less than, that was the justification.
In follow, a lot of this contemporary infrastructure was constructed for the French themselves, whereas the Vietnamese inhabitants continued dwelling in significantly much less sanitary circumstances.
And one specific piece of infrastructure, supposed to reveal the prevalence of French engineering, ended up producing one of the crucial spectacular backfires I’ve come throughout.
It concerned sewers, lots of of 1000’s of rats, and a authorities coverage that by some means made the issue even worse.
The French arrive with grand plans
Paul Doumer, governor-general of French Indochina from 1897 to 1902, wished Hanoi to turn into a powerful image of French colonial achievement.
Historian Michael G. Vann describes how Doumer envisioned a rational, orderly metropolis, in distinction to Saigon, which he considered disorderly and dominated by business pursuits.
French colonial officers have been satisfied that their civilization, science, know-how, training and administration have been superior and must be launched to the populations they dominated.
France had established colonial management over Hanoi within the Eighteen Eighties, and by 1902, the French had spent years reshaping it.
Hanoi was already a centuries-old Vietnamese metropolis, with its personal structure, traditions and established methods of dwelling.
However that wasn’t the form of metropolis Doumer wished to showcase.
He wished European-style streets, spectacular authorities buildings, and trendy sanitation methods that may reveal what French engineering might accomplish.
Town itself was meant to turn into proof that colonialism was helpful. With that, the French started working.
The outcome was magnificent. For some.
The transformation was spectacular, and you’ll nonetheless see a lot of the French architectural affect in Hanoi at this time.
The colonizers constructed broad, tree-lined boulevards, fancy European-style villas, authorities buildings and exquisite public areas.
Additionally they constructed one thing notably vital: an elaborate underground sewer system.
By the start of the 20 th century, there have been greater than 15 kilometers of sewer pipes beneath the European quarter.
Alongside the best way, the French demolished or remodeled elements of the present metropolis, together with spiritual and different historic websites, to make room for his or her imaginative and prescient.
The brand new French Quarter seemed splendid, and sanitation had actually improved for the folks dwelling there.
Besides these folks have been principally the colonizers themselves.
Rich European residents loved working water, flush bogs and trendy drainage methods, whereas many Vietnamese and Chinese language residents within the Outdated Quarter continued counting on public fountains and staff who collected human waste in buckets earlier than daybreak.
Through the wet season, drains within the older neighborhoods might again up, sending sewage into the streets the place Vietnamese residents lived.
Vann, who extensively researched the Hanoi rat marketing campaign, additionally discovered that Vietnamese taxpayers helped finance town’s modernization, regardless that the enhancements disproportionately benefited the European quarter.
So, sure, Hanoi had been remodeled.
However the advantages weren’t shared equally.
The rats liked the brand new metropolis, too
I’ve lived in Southeast Asia for 12 years and traveled extensively across the area, together with Vietnam.
It’s not unusual to see a rat or two sneaking round at night time, notably close to markets or areas concerned within the meals commerce. I see this in São Paulo, too, so that is in no way unique to Asia.
To me, it’s all the time appeared like a big-city drawback, nothing extra.
French directors, nevertheless, had typically regarded rat infestations in Hanoi’s Vietnamese neighborhoods as proof of poor native hygiene.
So long as the issue remained in these neighborhoods, it didn’t appear to concern the Europeans fairly as a lot.
With out meaning to, the French had created a paradise for rats.
The underground pipes supplied darkness, shelter from predators, and loads of alternatives to breed.
And whereas the French celebrated their trendy infrastructure, the rodents found that it supplied one thing else: an environment friendly transportation community.
The rats might journey beneath the streets and discover their manner into the European houses.
In keeping with Vann, there have been even stories of rats rising by way of the plumbing and bogs.
And whose houses have been these?
The French residents’ houses, after all.
The very individuals who had celebrated the brand new sanitation system as proof of European superiority have been now discovering rats in their very own loos.
What had beforehand been dismissed as a Vietnamese drawback was all of a sudden a European one.
The worry of plague
The timing made the infestation notably terrifying. In 1894, Alexandre Yersin recognized the bacterium chargeable for bubonic plague throughout an outbreak in Hong Kong. 4 years later, Paul-Louis Simond revealed analysis supporting the position of fleas in transmitting the illness.
These discoveries have been altering how docs understood plague, though a number of the particulars of its transmission have been nonetheless being debated.
The third plague pandemic was spreading internationally, with infections reaching new locations by way of business and transportation routes.
The French authorities have been nervous that rats showing in European houses might carry contaminated fleas and unfold the lethal illness.
They might ship staff underground and exterminate as many rats as potential.
However who would perform this harmful, disagreeable work?
Not the French residents themselves.
They employed native Vietnamese staff.
The good Hanoi rat hunt
Within the spring of 1902, the colonial authorities despatched groups of Vietnamese staff into the sewers to kill rats.
In keeping with Vann, the racial hierarchy of French colonial society meant that harmful, soiled guide labor was typically assigned to Vietnamese staff.
The rat catchers needed to navigate slender, darkish underground passages, transfer by way of human waste, and deal with wild animals which may carry illness.
Their compensation trusted the variety of rats they killed.
Between 26 April and 1 Might 1902, staff turned in 7,985 rats.
On 30 Might alone, they killed a reported 15,041.
And on 12 June, the authorities recorded an astonishing 20,114 rats killed in a single day.
These figures come from colonial administrative information examined by Vann, who found the bizarre rat-killing tallies whereas researching Hanoi’s historical past within the French archives.
The information counted the rats being killed, however they couldn’t inform the authorities what number of extra have been nonetheless dwelling beneath town.
The sewers nonetheless supplied a cushty habitat for the surviving rodents, and the infestation continued.
The French had complaints. So did the Vietnamese.
On 9 June 1902, simply three days earlier than the extraordinary rat rely, the resident-superior of Tonkin contacted the governor-general’s workplace about complaints from European residents.
Apparently, some French folks have been sad in regards to the sight and odor of Vietnamese staff rising from the sewers and strolling by way of their neighborhoods carrying useless rats.
The Vietnamese males have been doing the damaging, filthy work of defending European neighborhoods from illness, and a number of the folks being protected have been complaining about having to see them.
On 16 June, Dr. Serez, the pinnacle of well being companies, responded that the rat catchers have been no dirtier than strange sewer staff. He added that he had not personally acquired complaints about them.
The Vietnamese staff, in the meantime, weren’t notably completely satisfied both.
Their work was troublesome, disagreeable and probably harmful, they usually believed their pay was insufficient.
Throughout June and July 1902, they started organizing work stoppages and slowdowns.
The authorities finally needed to improve their fee from one cent per rat to 2 cents. By 1904, the speed had reached 4 cents per rat.
This wasn’t the general public rat-tail bounty that may turn into well-known later. It was the fee system used for the employed sewer crews.
Lengthy earlier than the broader inhabitants discovered methods to take advantage of the federal government’s bounty scheme, Vietnamese staff had already demonstrated that they might manage and discount with their French employers.
The authorities elevated the funds and continued killing rats. However the infestation wouldn’t disappear.
So that they got here up with one other thought. Why not get your complete inhabitants concerned?
The Vietnamese discover a enterprise alternative
The French administration determined to increase its rat-killing marketing campaign to most people. Residents might earn one cent for each rat tail they submitted.
Officers didn’t need folks bringing complete useless rats into authorities workplaces. Dealing with 1000’s of carcasses would create an infinite burden.
So that they determined that tails alone would rely as proof.
One tail, one supposedly useless rat, one fee.
With that, 1000’s of tails started arriving at municipal workplaces.
However then officers started noticing rats working by way of Hanoi’s streets with out tails.
As Vann describes in his authentic analysis, some residents had realized they didn’t truly have to kill a rat to assert the reward.
They might catch it, lower off its tail, ship the tail, gather their cash, and launch the animal alive.
The rat might then proceed breeding.
And a few folks reportedly went even additional.
In keeping with Vann’s historic analysis, well being inspectors found that individuals in villages outdoors Hanoi have been truly elevating rats for the aim of accumulating the bounty.
In a later interview with World Historical past Linked, Vann additionally described a black market by way of which rats have been introduced into Hanoi from elsewhere in northern Vietnam.
The French had launched a system that was supposed to cut back town’s rat inhabitants. As a substitute, they’d created an financial alternative across the animals themselves.
There’s one qualification value noting. Vann’s 2003 paper cites a municipal report from 1930–31 for the rat-farming account, with out establishing the precise date or location of the invention. The underlying report could be wanted to settle these particulars.
Some Vietnamese residents had responded creatively to an financial alternative created by the very administration that thought-about itself extra superior.
The authorities thought they have been paying for every exterminated rat, however in actuality, they have been paying for every rat tail.
Vann himself identified the irony of a colonial administration that inspired capitalist growth and entrepreneurship, solely to search out Vietnamese residents making use of that entrepreneurial spirit to its personal disastrous coverage.
Confronted with abuses of the bounty scheme, the French finally deserted it.
The ultimate irony
In late 1902, French officers opened an elaborate colonial exhibition in Hanoi.
The exhibition, which continued into early 1903, was supposed to reveal the achievements of French rule in Indochina.
An authentic report in regards to the exhibition describes ambitions to develop business relations and show the area’s assets, progress and future.
At its heart stood the Grand Palais, a powerful constructing supposed to indicate what French structure, engineering and administration might accomplish.
Above floor, the French have been celebrating the fashionable metropolis they’d created.
Under floor, its sewers have been nonetheless offering shelter and passageways for rats.
However there might have been one other consequence of the exhibition.
Vann means that the arrival of tourists and cargo for the occasion might have helped introduce plague-infected rats into Hanoi, probably contributing to the outbreak that adopted. The particular route was not conclusively established.
In 1903, Hanoi skilled a severe outbreak of bubonic plague.
In keeping with the colonial information examined by Vann, 159 instances have been formally reported among the many indigenous inhabitants, with 110 deaths. Amongst Europeans, six instances and two deaths have been recorded.
The true Vietnamese dying toll might have been greater, as some households reportedly hid instances and deaths to keep away from interference from the colonial authorities.
The bounty scheme itself can’t be proven to have brought on the outbreak. However the huge rat-killing marketing campaign had not eradicated the menace.
And the rats continued troubling the French authorities for many years afterward.
In his analysis on France’s longer battle towards rats, historian Peter Soppelsa describes one other rat-bounty drawback reported in Paris in 1939.
I contacted Soppelsa, an affiliate professor on the College of Oklahoma, to ask whether or not French officers had been conscious of Hanoi’s earlier expertise.
“I’ve no proof that Parisians in 1939 have been conscious of the sooner rat breeding in Hanoi,” he informed me in an e-mail on 21 October 2026.
However he additionally pointed me towards examples from Dutch colonial Java and Japan, together with a Japanese newspaper article from January 1900 that, in keeping with him, had already anticipated how folks dwelling outdoors cities would possibly exploit city rat bounties.
That warning got here two years earlier than the Hanoi marketing campaign. I’ve not but examined the unique newspaper article, so its exact wording stays unverified.
Right this moment, the Hanoi story is commonly used for instance an issue referred to as the cobra impact, during which a poorly designed incentive encourages the very conduct it was supposed to stop.
However I feel there’s something much more fascinating right here than an economics lesson.
The French arrived satisfied they’d the scientific information, engineering abilities and administrative energy to remodel Hanoi into a greater metropolis.
They rebuilt its streets, created trendy infrastructure, and confidently measured their achievements.
But their prized sewer system helped create a brand new rat drawback, the Vietnamese staff despatched to unravel it protested their circumstances, and a few residents found methods to revenue from the federal government’s answer.
The administration might report precisely 20,114 useless rats on 12 June 1902.
What it couldn’t reliably measure was whether or not its grand plan was truly working.
Sources and additional studying
- Michael G. Vann (2003). Of Rats, Rice, and Race: The Nice Hanoi Rat Bloodbath, an Episode in French Colonial Historical past. French Colonial Historical past, 4, 191–203. Authentic archival analysis.
- Michael G. Vann (2018). Interview with Marc Jason Gilbert. World Historical past Linked, 15(2).
- Ivan Franceschini and Michael G. Vann (2020). The Nice Hanoi Rat Hunt: A Dialog with Michael G. Vann. Made in China Journal.
- Peter Soppelsa (2021). Shedding France’s Imperial Warfare on Rats. Journal of the Western Society for French Historical past, 47.
- T. Butler (2014). Plague Historical past: Yersin’s Discovery of the Causative Bacterium in 1894. Medical Microbiology and An infection, 20(3), 202–209.
- Exposition d’Hanoï 1902–1903: Rapport général. Modern exhibition report, digitized by the Conservatoire nationwide des arts et métiers.
- Peter Soppelsa, private e-mail correspondence, 21 October 2026. Authentic reporting on rat-bounty examples in France, Dutch colonial Java, and Japan.
