Today, as the world grapples with the COVID-19 pandemic and as the death toll steadily mounts, a look back to the past is in order to gain insight and guidance about the impact of deadly contagions on peoples and their leaders. How have leaders and those they led responded to the shock of widespread illness? How have societies been changed by the ravages of disease? How has sickness affected leaders? What part has pandemics played in the rise and fall of great powers? How, indeed, does disease bend the arc of history?

The Greek general and historian Thucydides addressed these questions in his famous history of the Peloponnesian War. Writing almost 2,500 years ago, Thucydides made the ravages of a plague’s outbreak a major feature of his tragic narrative of the decline and fall of the Athenian Empire. The plague hit Athens when it was engaged in a desperate struggle against their arch great-power enemy Sparta. A citizen of Athens, Thucydides witnessed how the plague ravaged his homeland and the Athenian Empire over several years. Perhaps a quarter of the Greek population settled along the shores of the Aegean succumbed to the plague. Thucydides himself contracted the plague. He survived to provide a detailed and chilling description of its symptoms.

One victim of the plague was Pericles, the Athenian statesman and war leader. His celebrated, stirring funeral oration extolled Athenian democracy and civic virtue. Alas, Pericles’s paean to democracy is followed in Thucydides’ history by a gripping account of the breakdown in public order among the Athenian people stricken with the plague. Thucydides recounts: “No fear of God or law of man deterred a criminal. Those who saw all perishing alike, thought that the worship or neglect of the Gods made no difference. For offences against human law no punishment was to be feared; no one would live long enough to be called into account.” Instead of funeral ceremonies following traditions of respectful custom and practice, the bodies piled up and the Athenian people “buried their dead as best they could.” Thucydides lamented that, for fear of the contagion, people did not visit one another and “the sufferers died in their solitude.” His account strikes a somber chord with us today, as we hear of COVID-19 patients passing away alone, bereft of family and friends in the hour of their death. 

While Athens suffered a devastating loss of life, the plague largely spared the Peloponnesian League of Greek states led by Sparta. Thucydides records that the plague “did not spread into the Peloponnesus in any degree worth speaking of, while Athens felt its ravages most severely.” The plague’s strategic effects thus were asymmetric, favoring Sparta the totalitarian state over Athens the democracy in this protracted conflict among the warring states of ancient Greece.

Despite the beating inflicted by the plague, the Athenian people showed amazing resilience, renewing their power to keep on fighting. The shock and demographic disaster done to them by the plague did not defeat Athens. In Thucydides’ telling of the war, it was not the plague that defeated Athens; it was the poor strategic choices made by the Athenian people and their elected leaders that ultimately brought their downfall in the contest with Sparta. Still, the plague must surely have weakened Athens, depriving it of leadership and sources of strength that might have proved decisive in the great-power struggle against Sparta for mastery of the Greek world. 

Closer to our own time, a little more than a hundred years ago, the horrific influenza pandemic killed tens of millions of people around the world during the final year of the First World War and in the conflict’s immediate aftermath. In the Great War, influenza did not confine itself to only one side of the struggle: the malady crossed the frontlines, victors and vanquished alike suffered. German soldiers on the offensive on the Western Front in France during the spring of 1918, in a vain attempt to win the war by breaking through Allied lines, became ill. German military leaders maintained that the flu sapped the physical strength of their soldiers and contributed to the failure of their offensives that would have won them the war. That these offensives actually accelerated Germany’s defeat would be denied by the German generals, who found in influenza a handy excuse to cover up and shift the blame for their own mistakes in strategy. 

Meanwhile, on the other side of the trenches, the spreading influenza pandemic battered the American army mobilizing at home and hastily deploying overseas to Europe. Almost as many American soldiers died from influenza as were killed in combat. Among Britons, an estimated 150,000 died from influenza. That number of fatalities is more than the number of British soldiers killed in the two hideous battles of the Somme in 1916 and at Passchendaele in 1917. Influenza was truly a plague on both houses fighting the Great War. 

As in ancient Athens, the influenza pandemic afflicted all levels of society: leaders were not immune. In September 1918, the flu hit Britain’s prime minister David Lloyd George on a visit to Manchester, where he had traveled for a crowded program of speeches and ceremonies. Stricken by the flu, the fifty-six-year-old British prime minister had to cancel his public events: he was much too ill to carry on. The flu kept him locked in bed in Manchester for two weeks, putting him out of action during a critical period in the war when the German army was getting mauled on the battlefield and the prospect of an early end to the fighting became a real possibility. Frustrated and angry, the British prime minister saw himself as needed to negotiate the terms for ending the fighting, and he could not afford to be an invalid at such a momentous time. Confined to bed, Lloyd George was “chafing like a caged lion.” 

Lloyd George’s medical condition was touch and go. His family feared for his life, and wife Margaret stayed close by his side while he slowly recovered. One close confidant recorded that Lloyd George “had a nasty illness which has shaken him a good deal.” In public, the government downplayed the seriousness of the prime minister’s condition for fear of undermining the morale of the British people when the tide of battle had turned against Germany on the Western Front and victory seemed within sight.  

With the worst of Lloyd George’s illness over, his wife Margaret returned to their home in Wales for a well-deserved rest. Alas, while at home, apart from her husband, she contracted the flu. The stoic Margaret hid her illness from him, believing there was nothing that he could do to make her better and determined not to worry him while he was resuming his duties as a war leader. Only after she recovered did Lloyd George find out about his wife’s illness by reading about it in the newspaper. Lloyd George and his wife offer an extreme example of social distancing within a marriage. 

In addition to his wife, the other woman in Lloyd George’s life, his confidential secretary and mistress Frances Stevenson, became ill. While very much missing Frances, the prime minister admonished her: “Don’t be in too great a hurry to get well. It leads to fretting & impatience & overpersuading nurses & doctors to let you do things you ought not to—and ultimate disappointment. Climb back to strength slowly.” Certainly good advice from an adoring and amorous prime minister to his private secretary! 

Another prominent leader who almost died during the influenza pandemic was Franklin D. Roosevelt. As Assistant Secretary of the Navy in the Woodrow Wilson administration, the 36-year-old Roosevelt traveled to Europe during the summer of 1918 as part of a fact-finding mission to see how the United States could best support Britain and France in the fight against imperial Germany. He arrived at a desperate moment in the war, when the German army was still on the offensive in a bid to break through the Allied lines on the Western Front before American forces could arrive in strength to tip the balance of power against Germany. In addition to inspecting the American effort in Europe, Roosevelt sought to reassure his hosts, the leaders of Britain and France, that the United States was committed to total victory over Germany. At a special dinner in London, he told an audience of British notables (that included Winston Churchill, then serving as Britain’s minister of munitions): “We are with you to the end.”

Alas, as Roosevelt departed from Europe for home, he became ill with a high fever. He was sick during the whole voyage across the Atlantic. His condition worsened, and he developed pneumonia in both lungs. Upon arriving stateside, he was so ill that he had to be carried in a stretcher off the ship. His boss, Secretary of the Navy Josephus Daniels, concerned for Roosevelt’s life, ordered an ambulance to convey him from the ship to his mother’s home in New York City. While recuperating, Franklin received a note from former President Theodore Roosevelt: