Winston Churchill wrote this about becoming prime minister in May 1940 during what some have called Britain's darkest hour:
As I went to bed at about 3 a.m., I was conscious of a profound sense of relief. At last I had the authority to give directions over the whole scene. I felt as if I were walking with destiny, and that all my past life had been but a preparation of this hour and for this trial. . . . I thought I knew a good deal about it all, and I was sure I should not fail.
Soon enough, Churchill would refer to this period, in which Britain, her skies defended by men in their twenties and her people bloodied, battered, and bruised by nightly bombardments, stood alone against Nazi Germany, as her "finest hour." It was a phrase that historians would later use to describe his performance as leader.
How did he do it? His own words just cited give a good indication. He knew a "good deal": His two stints as First Lord of the Admiralty, plus his time as minister, had given him insight into how the military and government must coordinate their efforts. He had the "authority to give directions": He had led men in battle, in government service, and in Parliament. He was one with "destiny": As a historian and an avid reader, he measured himself against the legacies of great leaders in wartime. He was confident: "I was sure I should not fail." As historian Geoffrey Best amply illustrates in his one-volume meta-biography, Churchill had been preparing for this challenge for his entire life: as soldier, parliamentarian, minister, historian, and journalist.
What Churchill's words do not say, but imply, is this: He was a born communicator. He knew how to describe a scene, present a point of view, and tell a good story. He also, as his biographer Geoffrey Best writes, put his audience at the center of the action. During his speeches and broadcasts of the war years, he positioned the British people at the center of the world; he spoke to them as actors on the world stage. By so doing, he made them feel a sense of importance—or, as we would say today in management, encouraged them to take a position of ownership of the issue. When this occurs, people have a sense of their own destiny; during any great event, such as a war, people may feel a sense of insignificance, a sense that they have no ability to affect the outcome. Churchill's speeches counteracted that sentiment as he spoke again and again of the individual contributions of the British people at home or abroad.
Churchill made certain that his message got through. His speeches in Parliament were of course widely covered. And when he took to the airwaves, people stopped what they were doing, whether at home or at work, to listen. He courted the press barons of his day, in particular Lord Beaverbrook, making him a member of his Cabinet.
Churchill also made frequent use of memos, or, in his parlance, "minutes." Reading samples of them, one gets the feeling that he was totally immersed in the activity, quick with suggestions or requests for follow-up. His memo writing enabled him to use his pen when he did not have the luxury of face-to-face communication. These memos also documented what occurred and what follow-up actions resulted. Again and again, Churchill insisted on written communications for precisely this reason: He wanted to be in the loop on important decisions.
Churchill was direct and straight with his people. He did not hide the dangers that faced the island kingdom in the dark days of 1940. As he told the House of Commons in his first speech after becoming prime minister,
I would say to the House, as I said to those who have joined this government: "I have nothing to offer but blood, toil, tears, and sweat."
We have before us an ordeal of the most grievous kind. We have before us many, many long months of struggle and of suffering. You ask, what is our policy? I can say: "It is to wage war, by sea, by land, and air, and with all our might and with all the strength that God can give us."
Ever the realist, Churchill knew that he could not simply deliver a challenge. He had to sketch his vision of the end—a note of inspiration in a time of desperation.
You ask, what is our aim? I can answer with one word: It is victory, victory at all costs, victory in spite of all terror, victory, however long and hard the road may be; for without victory, there is no survival. Let that be realized; no survival for the British Empire, no survival for all that the British Empire has stood for . . . and I say, "come then, let us go forward together with our united strength." 
With that speech, which is brief by Churchillian standards, he rallied Parliament, which had not been favorably disposed toward him. As he closed, he, along with the House, was in tears. This speech was also the beginning of the metaphysical union between Churchill and the British people that would endure throughout the war. As philosopher Isaiah Berlin essayed,
The Prime Minister was able to impose his imagination and his will upon his countrymen . . . precisely because he appeared to them larger and nobler than life and lifted them to an abnormal height in a moment of crisis. [In doing so] it did turn a number of inhabitants of the British Isles out of their normal selves [and capable of heroism].
One way in which Churchill maintained unity with his people was by meeting and mingling with them. From his earliest days, he had had a love of action. As prime minister, he took it upon himself to make frequent "flying visits" to the front in North Africa or Europe, to America to press British interests with the Roosevelt administration, and even to Moscow and Yalta to negotiate Soviet support during the war and stem Soviet aggression in the postwar era. Another kind of flying visit was to his own people. He visited the London Docklands area, which was heavily bombed during the Blitz, and even risked his own life when he stayed until nightfall and was caught in the middle of a raid. Never lacking in courage, Churchill believed it was important that he both see the damage firsthand and be seen as a leader who was one with his people.
Winston Churchill, The Second World War, vol. 1, The Gathering Storm (New York: Houghton-Mifflin 1948), quoted in Geoffrey Best, Churchill: A Study in Greatness (London and New York: Hambledon & London, 2001), pp. 165-166.
Geoffrey Best, Churchill: A Study in Greatness (London and New York: Hambledon & London, 2001), p. 187.
Ibid., pp. 197-199.
Eliot A. Cohen, Supreme Command: Soldiers, Statesmen and Leadership in Wartime (New York: Free Press, 2002), p. 124.
Winston Churchill, "First Speech as Prime Minister," Complete Speeches of Winston Churchill.
Best, Churchill, p. 187. [Cited in Mr Churchill in 1940 London: John Murray, 1948 p.29.]
Cohen, Supreme Command, p. 120.
Ibid., pp. 124-127.