A good speech from a great leader can change the world. After the Battle of Gettysburg, Abraham Lincoln delivered the Gettysburg Address, a speech that strengthened the resolve of the Union to continue fighting battles like that for another two years. After the Japanese attack on Pearl Harbor, President Franklin Roosevelt told the American people that day would live in infamy, and it has ever since.

But it might surprise you to discover that some of history's greatest lines were improvised by the speaker, instead of written into the script of the age.


1. President Bush's Ground Zero "Bullhorn Speech"

George W. Bush has been accused of a lot of things, but being one of history's greatest orators is not one of them. Still, in the days following the Sept. 11 attacks, the United States needed its fearless leader to show up at the center of it all and encourage the nation to stand tall, and George W. Bush was able to do that. What started out as an impromptu, unprepared remark about empathy turned into one of the most memorable speeches of modern presidential history when a worker in the back shouted, "we can't hear you," referring to the president's bullhorn.

President Bush, contrary to what some might believe, is quick on his feet and responded with the legendary line "I can hear you. The whole world hears you. And whoever knocked down these buildings will hear all of us real soon."

2. Martin Luther King's "I Have a Dream" Speech

Dr. Martin Luther King Jr. walked to the podium on Aug. 28, 1963, intent on sticking to the script. His prepared remarks mentioned nothing about the dream King had. He'd mentioned the dream speech before, but was convinced the speech wouldn't have the same effect on such a gathered crowd for such a long speech. In the middle of the speech, Gospel singer Mahalia Jackson shouted to Dr. King, telling him to use the "dream" line.

At around 12:00 above, you can see the shift in Dr. King's face. He stops looking down at his notes as he had for the previous 12 minutes and begins to address the crowd directly, flawlessly delivering the "dream" portion of the speech. This part of the speech is much less measured and more emotional than a banking analogy.

3. Winston Churchill's "The Few" Speech

By August 1940, Britain stood alone in Europe against the Nazi war machine. Poland and France had already fallen, and the only things protecting England was the English Channel and the Royal Air Force. British airmen were giving everything they had to defend the island nation from the relentless attacks of the Nazi Luftwaffe, day and night, and they were running low on planes and pilots. Churchill was moved by the pilots who survived the bombing of an RAF airfield just days before and told the assembled men that 'never in the history of mankind has so much been owed by so many to so few.'

He delivered a speech on that to Parliament on Aug. 20, 1940.

4. George Washington "Grows Blind"

(Smithsonian Institution)

The Continental Army was growing restless in 1783. Victory in independence was just around the corner, but they didn't know that. They were upset at having not been paid by Congress. Officers and soldiers of the army decided to meet in Newburgh, N.Y. to draw up a letter to Congress. Their demand was to be paid or warn the body of a coming mutiny. When George Washington heard about it, he decided to address the men on a day of his choosing.

When he entered the hall, he entered through a side door instead of the main door and proceeded to give a nine-page speech warning them against such a mutiny. He also expressed support for their sentiments and went to share a letter from a Congressman who shared it too. As he pulled out the letter, he also pulled out his glasses and said the immortal words:

"Gentlemen, you must pardon me. I have grown gray in your service and now find myself growing blind."

It was that improvised line that prevented the mutiny, reaffirmed their loyalty to their graying commander, and won the war.