Napoleon, Empress Wu, Franklin D. Roosevelt, Oliver Cromwell, Akbar, Stalin. History provides many examples of strong leaders who left their marks, for better or for worse.

But what the past will not do is provide the magic formula for how to become an effective leader. Looking for clear lessons in history is a futile quest: there are too many and their meaning is always in dispute. History can be useful, however, in suggesting patterns and parallels, raising questions, and – equally important – giving warnings about why things go wrong.

From top left: Winston Churchill, Emperor Charles V, Mustafa Kemal Ataturk, Franklin D. Roosevelt

So here, from one historian, are first some tips about what goes into the making of a successful leader and, second, warnings about what can bring failure.

You have to want to lead

Leading can be gratifying, often exhilarating, but it is also lonely. Ambition and the determination to succeed may mean sacrificing friends and family. Think of how many children of great men have had unhappy lives. That loneliness is why statesmen like summits: they meet those rare others who face the same pressures and responsibilities.

At the Paris Peace Conference of 1919, David Lloyd George of Britain, Georges Clemenceau of France and Woodrow Wilson of the United States talked about their dreams and shared their fear of failure. What they also had in common was an ability to pick themselves up after setbacks and keep on going.

Work out the key people to keep on side

The people to keep on side can vary: in a democracy, leaders need to worry about numbers and getting re-elected; in an authoritarian state, leaders can probably just focus on keeping certain institutions – the military or the secret services, for example – on side.

When Bismarck created Germany he needed one man above all others: the Prussian King Wilhelm. It was not an easy relationship – Wilhelm complained that it was hard to be king under Bismarck – but in the end he supported his brilliant minister, who in turn made him Emperor of Germany. In democracies, political leaders have to build stable coalitions. After the Great Depression in the United States, the Democrats brought together Southern Whites, Northern Blacks, the working classes and liberals, and that served them well for decades.

It helps to be a good communicator

That means above all understanding your audience.

Lloyd George, who was one of the greatest British orators, once said: “I reach out my hand to the people and draw them to me. Like children, they seem then.” Winston Churchill’s rhetoric in the Second World War can sound overblown today, but it was what the British people needed at the time.

Oh, and it does make a difference to have something to say. In his radio Fireside Chat of the 1930s and 1940s, President Roosevelt was reassuring the American people about the state of the nation and getting them used to the idea that the United States might have to fight the dark forces gathering in Europe and the Far East.

It also helps to listen

In the Cuban Missile Crisis, perhaps the single most terrifying moment of the Cold War, President John F. Kennedy insisted on hearing his advisers’ different points of view before deciding how to deal with the Soviet challenge in Cuba. (Interestingly he had also just read Barbara Tuchman’s classic book on the outbreak of the First World War, which showed how easily leaders can make mistakes and stumble into a conflict they didn’t really want.) As Kennedy also demonstrates, choosing good and independent subordinates is a safeguard against making bad decisions.

If you can intuit the way the currents of history are flowing, you may be able to ride them

Bismarck famously said that a statesman “must wait until he hears the steps of God sounding through events, then leap up and grasp the hem of his garment”. And he did that when he manoeuvred across the chess board of Europe to create the new state of Germany.

Effective leaders are able to manage both the day-to-day issues that press in on them and the bigger picture. That is where a knowledge of history helps, as it shows patterns amidst all the noise of current events and reminds of possibilities other than those we are used to.

And now for some warnings.

Beware of the traps that power lays

The French talk about “déformation professionnelle”, which means the way your profession or your post can subtly warp your judgement so that you only see things from one perspective.

Before the First World War, the German General Staff were told to develop plans to ensure Germany’s victory, if necessary against France and Russia at the same time. They came up with a brilliant and detailed plan to fight a holding action against Russia in the East and, by throwing the bulk of their forces against France in the West, bring its surrender rapidly. Because it made military sense, German troops would invade neutral Belgium on their way to Paris. Politically, though, it was a disastrous decision. Germany’s violation of Belgian neutrality brought Britain into the war, virtually ensuring its defeat.

Power is also dangerous, because those who hold it start to think they can do whatever they choose. Think of Richard Nixon trying to use the institutions of the American government to shut down the Watergate scandal. Or the American war in Vietnam. In the 1960s the United States was the most powerful economic and military power in the world. Its leaders assumed they could easily overwhelm North Vietnam and bring its leaders to the bargaining table. They did not bother to wonder whether their enemies (and their Vietnamese allies) might have different ideas. Robert McNamara, who was Secretary of Defence at the time, later said, “Our misjudgements of friend and foe alike reflected our profound ignorance of the history, culture and politics of the people in the area and the personalities and habits of their leaders.”

Don’t start to believe your own propaganda

In ancient Rome, when a successful leader enjoyed a triumphal march, a slave stood behind him and whispered in his ear: “Remember you are human.” Mustafa Kemal Ataturk, the father of modern Turkey, was the rare leader possessing great power who knew his own limitations. It is said that he issued a standing order that any instruction he gave in the evenings – when he liked to carouse with his friends – should be ignored.

History has far more examples of leaders whose conviction of infallibility grow in proportion to their power. With most of Europe lying at his feet, Napoleon came to think he was invincible. He found himself enmeshed in a pointless and costly war in Spain. Then to bring the young Tsar Alexander to heel he invaded Russia, the mistake that led to his eventual downfall.

Adolf Hitler had a string of successes – the seizing of Austria and Czechoslovakia, the defeat of France, the partition of the centre of Europe with the Soviet Union – which convinced him that he was infallible. Against his generals’ advice he followed Napoleon into Russia. When German troops encountered resistance, Hitler refused to let them retreat. It was the beginning of the end.

Know when to step down

Relinquishing power is one of the hardest things to do. Yet, as the old joke has it, graveyards are full of people whose tombstones read: “They thought they were indispensable.” The 16th century Emperor Charles V who voluntarily abdicated as Holy Roman Emperor and retired to a monastery is highly unusual.

Far more often, leaders have chosen to stay on when they should have bowed out. Without intending to, they often undo much of their own work and cause problems for their successors. An old and increasingly frail Winston Churchill should not have tried to be prime minister again in 1951. His government drifted, while his chosen successor Anthony Eden grew increasingly embittered.

A final word: You can have all the qualities that make a great leader – from determination to vision to sheer ability – but if you don’t have luck and good timing, you will never get a chance to show what you can do.