The disastrous effects of the Russian invasion on Napoleon Bonaparte’s Grand Army (Grande Armée) are well known. Less known are the reasons for their defeat. Genetic evidence proves that Pediculus humanus corporis, otherwise known as body lice, had a key role in the debacle, although the Russian resistance, brutal weather and the lack of food and water contributed to its decimation.
Researchers from the University of the Mediterranean, Marseille, France, led by Dr. Didier Raoult, unearthed a bag of material containing 2 kg of bone fragments, clothing remnants, and segments of body lice from soldiers buried in a mass grave in Vilnius, the capital of Lithuania. Analysis of the material proved that almost one-third of those buried there were affected by louse-born infections such as typhus and trench fever.
Raoult and his colleagues studied segments of body lice as well as the dental pulp from soldiers’ teeth. The dental pulp revealed DNA from Rickettsia prowazekii, the agent that causes epidemic typhus, whose size is that between a bacterium and a virus. When lice are fed upon a typhus patient during the febrile period of the illness, and even after a few days afterwards, a large proportion of them becomes infected and can transmit the disease by the louse bite. If the DNA of such pathogen is present in teeth, Raoult’s team concluded, it is very likely that the organism was the cause of death.
Napoleon’s wrong decisions
Napoleon marched into Russia in 1812 with more than 500,000 soldiers, leading what up to then had been Europe’s largest army. The Russian army numbered around 200,000 soldiers. He disregarded his commanders’ advice to be well prepared for the Russian winter. Napoleon told them that the Russian winter couldn’t be worse than the French winter to which his soldiers were used to. His commanders also advised him to conduct the military operation during late spring, where there wouldn’t be necessary to make special preparations. Napoleon told them that France’s glory couldn’t wait that long.
The problems started after passing Germany and reaching Poland, where Poland’s Surgeon General warned them that there were endemic foci of typhus throughout the country, and the disease was rife among the country’s peasants. His soldiers were strictly prohibited to fraternize with the Polish peasants, risking being punished with the death penalty. His orders were ignored, the soldiers made frequent raids into Polish homes looking for food and brought typhus with them to the camps. Tens of thousands of soldiers died as a result. Despite all these obstacles, the French army marched forward, the ultimate goal being Moscow.
Marching into Moscow
One decision that proved particularly costly was to continue the march toward Moscow despite tremendous loss of life during the march and his own generals’ desperate pleas to halt the invasion. Undaunted, Napoleon answered his generals: “The very danger pushes us on to Moscow. The die is cast. Victory will justify and save us.”
The Russian commanders thought that the problems by the French army found in Poland would be even worse in Russia, and decided not to engage the French in battle, but to draw them further into Russian territory, where their supplies would have difficulty in reaching them. In addition, the implacable Russian winter could conclude what the typhus epidemic had started. The French losses were enormous.
Despite all the losses throughout its march through Eastern Europe, the French army captured Moscow on September 14, 1812 with only 90,000 soldiers out of an initial force of more than 500,000. Conquering Moscow proved to be a Pyrrhic victory, for most of the capital’s citizens had already abandoned the city and set fire to it. There was almost no food, no shelter, and typhus raged among the soldiers. The only option was retreat. On December 14, 1812 the Grande Armée left Russia, in what was known to them as the Patriotic War of 1812.
A sad ending to a beautiful dream
Until recently, it had been assumed that Russia’s army and its brutal winter were the main causes of the French soldiers’ deaths. This idea had been buttressed by Napoleon’s report to the Senate on December 20, 1812: “My army has had some losses, but this was due to the premature rigor of the season.” He thus tried to deflect criticism of his bad decisions during the campaign.
Napoleon’s retreating army reached Vilnius, Lithuania, (which Napoleon had called “The Jerusalem of the North” because of its Jewish traditions). Only 7,000 soldiers and 20,000 stragglers remained. From there they continued their retreat, leaving the sick and wounded in Vilnius. Those who died there were buried in mass graves. Napoleon’s Grand Army was destroyed during the invasion of Russia. Of the more than 400,000 military deaths in the French army, 220,000 can probably be attributed to typhus. A great dream had become a great nightmare.
While historians believed that disease had played a big part in dooming the invasion of Russia, the investigation by Raoult and his colleagues provided the first solid evidence in support of this belief. The confirmation by a team of medical researchers that typhus transmitted by lice was one of the main reasons for Napoleon’s defeat shows the value of their genetic research in helping to reinterpret history. That Europe’s most powerful army was defeated by a humble microbe should be cause for sobering reflection in these troubling times.