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: 

Dear Franklin, 

We are deeply concerned about your sickness, and trust you will soon be well. We are very proud of you. 

With love, 

Aff. Yours 

Theodore Roosevelt 

It was during Franklin’s convalescence at home that his wife Eleanor, when she unpacked his luggage upon his return from Europe, discovered love letters from Lucy Mercer, who was the other woman in her husband’s life. Before the war, Mercer had served in the Roosevelt household as Eleanor’s social secretary. Eleanor had even considered Lucy a close friend. After the war’s outbreak, Lucy left service with Eleanor and joined the Navy. At the Navy Department, she received an assignment to work as a personal assistant to Franklin. 

In finding the letters, not only did Eleanor uncover the affair, but she also soon discovered that many in their social circle knew about her husband’s infidelities while she had been in the dark. The prominent Washington socialite Alice Roosevelt Longworth, Theodore Roosevelt’s outspoken daughter and Eleanor’s cousin, knew of the affair, even encouraged it, and spread the story in the nation’s capital. (Alice, known for her malicious wit, is reputed to have said that Franklin “deserved a good time. . . . He was married to Eleanor.”) 

Shamed and angered by these discoveries, Eleanor offered her husband a divorce. Roosevelt’s mother and his political handlers made clear to him, however, that divorce was out of the question because it would likely ruin his chances for a successful career in politics. While Roosevelt recovered from the flu and his marriage survived, Eleanor would never forget her husband’s betrayal and her humiliation. 

The influenza pandemic continued on its killing rampage around the world, even as the armistice brought an end to the fighting on the Western Front on November 11, 1918. In Paris during the first half of 1919, the flu infected the negotiations taking place to write the peace treaties that would bring a formal end to the war. Leaders and their staffs suffered under illness while the negotiations dragged on. One casualty of the flu was Sir Mark Sykes, the soldier and diplomat best known today for having worked up the Sykes-Picot agreement to partition the Middle East among the victorious powers. Sykes, only thirty-nine years of age, died in his hotel room in Paris where he formed part of the British negotiating team. 

President Woodrow Wilson became seriously ill when he came down with the flu at the beginning of April. Wilson’s doctor, Cary Grayson recorded that the president was “seized with violent paroxysms of coughing, which were so severe and frequent that it interfered with his breathing.” Wilson’s fever spiked to over 103, and Grayson feared for the President’s life. His wife Edith recorded that he suffered from a burning fever that incapacitated him, and she “was dreadfully alarmed.” 

When hit by the flu, the sixty-two-year-old president was engaged in diplomatic battles with the French, Italians, and Japanese over the peace treaties. In particular, Wilson labored in tough negotiations with France’s Prime Minister George Clemenceau, the two leaders disputing the terms of the peace treaty with Germany. The American delegation believed that Clemenceau, Lloyd George, and Italy’s Prime Minister Vittorio Emanuele Orlando would seek to take advantage of the President’s illness in these trying negotiations. For several days, Wilson was too ill to take part in discussions. Wilson’s wife Edith recorded: “He was too ill to rise from his bed. However, things were at such a crisis that he could not relax his personal hold.” She wrote adoringly about her husband that “the spirit was stronger than the flesh.” Once he started to recover, Wilson insisted on working from his hotel suite. He requested that “unless Clemenceau, Lloyd George and Orlando were afraid of the disease,” the negotiations should continue, taking place in his bedroom. To what extent Wilson’s illness affected his judgment in the final stages of negotiating the peace treaty with Germany remains disputed by historians. His staff, however, saw a marked change in the president's behavior. One aide thought “something queer was happening in his mind. One thing was certain: he was never the same.” 

If the flu had not hit Wilson in Paris, would he have fought harder to make the Treaty of Versailles more conciliatory toward Germany? Would more moderate terms in the treaty have reconciled the German people and their leaders to their defeat? We cannot know the answers to these questions. In light of Germany’s actions during the war, the Treaty of Versailles was not unduly harsh. After all, Germany had started the war by invading Belgium and France in response to a breakdown of the peace in the Balkans. The German occupation of conquered territories also had inflicted immense damage on them. In addition, the Treaty of Versailles reflected to a remarkable degree Wilson’s Fourteen Points, which he proclaimed would provide the basis for an enduring peace. The Fourteen Points called for Germany to lose territory and pay reparations. Furthermore, the victorious powers were justified and bound to limit the German armed forces so that Germany could not carry out offensive operations by land or by sea for the foreseeable future. A stable peace required that Germany not possess the power to wage future wars of aggression. For all its flaws, the Versailles settlement did not make inevitable another world war: a Great Depression leading to a vicious nationalist extremist movement seizing power in Germany were needed to bring on the next European conflagration. There was nothing inevitable about either the Great Depression or Hitler’s seizure of power coming to pass. The impact of the flu on Wilson’s judgment in negotiations thus was not as great as sometimes alleged. 

During the second half of 1919, when Wilson’s health collapsed, crippled by strokes, the impact on his judgment is more readily apparent. The breakdown in Wilson’s health ruined whatever hope he had of convincing the American people and their elected representatives in the Senate to ratify the peace treaty that he had negotiated in Paris. If Wilson’s health had held up, perhaps he might have proven more willing to compromise with political opponents at home, leading the United States to join the League of Nations and to underwrite European security. The strokes that crippled Wilson, more than influenza, wrecked his vision for America playing a greater role in world affairs. 

One prominent leader who managed to escape from the influenza pandemic was none other than Winston Churchill, Roosevelt’s future coalition partner in the next world war. Influenza was all around Churchill. As minister of munitions in the British government, he was a close political ally of Lloyd George when he came down with the flu in the autumn of 1918. In addition, Churchill attended the same dinner that summer in London where he and Franklin D. Roosevelt met for the first time. Those serving in a high office near Churchill, too, came down with the flu. In February 1919, the flu struck Air Marshal Sir Hugh Trenchard, who Churchill had selected to serve as the Royal Air Force’s chief of staff. Trenchard felt so ill that he tendered his resignation to Churchill, who at the war’s end had moved to serve in the British government as the civilian head of the Royal Air Force. Churchill refused the resignation offer, but it took almost two months before Trenchard was well enough to take up his duties as air force chief of staff. 

Influenza would strike even closer to Churchill when his own family became ill on no fewer than two separate occasions. Influenza first afflicted his household in March 1919, while Churchill was in France taking part in the peacemaking deliberations in Paris. His wife Clementine wrote to him: “I’m afraid I am in for influenza. My temperature this morning is 102.” Poor Clementine could not find a doctor to attend to the Churchill family because physicians and nurses were overextended treating so many people being sick at that time. The Churchill children’s nanny by the name of Isabel also was stricken by the flu. The nanny became delirious with fever and attempted to take Churchill’s youngest daughter Marigold, then only a few months old, into her bed. Clementine had to rescue the infant and keep her away from the fevered nanny. Clementine wrote to her husband that Isabel “talked fast & loud in an unearthly voice like a chant for several hours.” Despite Clementine’s best efforts to nurse the nanny, she died. Of the next few days, an ill Clementine fretted that her baby daughter might have caught the flu. Clementine wrote to Churchill: “I am unhappy.” When Churchill returned from France, he stayed away from the stricken household to avoid exposure to the contagion. 

The Churchill family would yet again come down with a flu-like ailment right after Christmas in December 1921. Once more, Clementine needed to cope with the emergency without her husband. This time, he was away in Cannes in the south of France, working hard at writing The World Crisis, his autobiographical history of the First World War. The day after he left for France, his family became ill. All three of the children had high fevers. Only four months earlier Winston and Clementine had lost their youngest child Marigold. The infant Marigold had survived the influenza pandemic, but she became ill with a sore throat that became infected during the summer of 1921. Poor Marigold passed away with both her distraught parents at her bedside. This recent sad loss of their youngest child must have weighed heavily on Clementine’s mind as her older children became sick. A determined Clementine quickly arranged for a doctor to visit and for two nurses to come and live in the home to provide full-time medical care for the family. In a long letter, Clementine detailed to her husband the efforts she made to protect their children. She sought to reassure him, for him not to be anxious because she and the children were being well looked after. “It is providential you went away as it would have been most annoying if you had caught it.” She wrote: “I do hope you are having a delicious time.” Clementine sick at home could only dream of the south of France. 

Churchill wrote back: “What a cataclysm! Poor darling I expect you have had an awful time. But as usual you have risen to the occasion & your letter about it all is Napoleonic.” From Churchill, to be described as Napoleonic was a high accolade, even if we do not typically associate the French emperor in the role of a mother caring for a sick child and a wife seeking to reassure her husband. Churchill could not help but feel pangs of guilt that he had dodged the flu bullet once again and was not around to help care for his family. “I feel a recreant hastening off to the Riviera and dwelling among these flesh pots while you are on the rack at home.” Since Clementine had arranged for nursing staff to watch over the children, Churchill recommended that she get bed rest. “A week on y[ou]r back will do you all the good in the world. Then come out here to recuperate in this delicious sunshine and let me mount guard in y[ou]r place over the kittens.” Little did the famous couple know but Clementine was likely pregnant with their youngest daughter Mary at this time when she was exhausted from looking after a household of sick children. 

While Churchill avoided contracting influenza during the Great War, he had given thought to the disease. He even wrote a poem about influenza almost thirty years before in 1890 when he was fifteen and a student at Harrow. The poem was a reflection upon an influenza epidemic that was then striking Russia. 

Oh how shall I its deeds recount 

Or measure the untold amount 

Of ills that it has done? 

This poem from the young Churchill certainly captures what we are all thinking today in trying to assess the political, strategic, and social effects, as well as the deeply personal human toll of contagion. 

While Churchill avoiding contracted influenza, he did come close to death in 1922 when he became seriously ill with appendicitis. He recalled: “I had a very serious operation performed only just in time, and an abdominal wound seven inches long.” The operation and recovery occurred at a crucial time when a nation-wide election was underway. His illness curtailed his ability to campaign, and his wife Clementine tried to act as a substitute while he remained confined to bed. When he finally did recover, his weakened physical condition hobbled his ability to conduct a vigorous election effort. The election result was not surprising: Churchill would lose his seat in Parliament, while the Liberal Party to which he then belonged went down in catastrophic defeat. This crushing personal and party election defeat tossed Churchill out from high executive office of state in the government. Putting on display his famous humor, he would write: “In the twinkling of an eye I found myself without an office, without a seat, without a party, and without an appendix.” 

These stories of leaders and illness raise sobering “what if” questions about the unfolding of history. What if the flu had taken Franklin D. Roosevelt as one of its victims in 1918, or if a burst appendix had killed Winston Churchill in 1922? Who would have served as President in bringing the United States out of the Great Depression? Who among American political leaders was better equipped than Roosevelt to lead the country during the Second World War? In the case of Britain, who would have better led the British people during its “finest hour” during the grim days of 1940 in standing up to the Nazi menace? To ask these uncomfortable questions is to highlight the role of chance, of individual leaders, of illness in history. But Churchill and Roosevelt did survive and lived to save Western Civilization from falling into an evil dark age as awful to imagine as any contagion. We are fortunate that their robust constitutions kept them alive to fight again another day. 

John H. Maurer serves as the Alfred Thayer Mahan Distinguished University Professor of Sea Power and Grand Strategy at the Naval War College in Newport, Rhode Island. The views expressed in this article are those of the author alone. 

Image: Wikimedia Commons