To celebrate his influence, here are extracts from some of his less-famous, but equally stirring speeches.
"When the opportunity presents itself for you to defeat your enemy, that is the time which you must not do it. There will come a time, in many instances, when the person who hates you most, the person who has misused you most, the person who has gossiped about you most, the person who has spread false rumors about you most, there will come a time when you will have an opportunity to defeat that person. It might be in terms of a recommendation for a job; it might be in terms of helping that person to make some move in life. That’s the time you must not do it.
"That is the meaning of love. In the final analysis, love is not this sentimental something that we talk about. It’s not merely an emotional something. Love is creative, understanding goodwill for all men. It is the refusal to defeat any individual. When you rise to the level of love, of its great beauty and power, you seek only to defeat evil systems. Individuals who happen to be caught up in that system, you love, but you seek to defeat the system."
Martin Luther King: Life in pictures
Martin Luther King: Life in pictures
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Martin Luther King during his famous 'I have a dream' speech in Washington in 1963
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Martin Luther King Jr at the Lincoln Memorial in 1963
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American civil rights campaigner Martin Luther King (1929 - 1968) arriving at London Airport. He is in England to be the chief speaker at a public meeting about colour prejudice and to appear on the BBC television programme 'Face To Face'
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Martin Luther King Jr. tells a Miami, Florida news conference, that he will go to Los Angeles to meet with black and white leaders and help create "a community of love" in the violence torn city in August 1965
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Martin Luther King Jr. and his civil rights marchers head for Montgomery, the state's capitol, March 21, 1965, during a five day, 50 mile walk to protest voting laws
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An image from 1960 shows Martin Luther King at a meeting
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Martin Luther King Jr. and his wife Coretta Scott King leading freedom marchers in Montgomery, Alabama in 1965
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Civil rights protestors marching from the Washington Monument to the Lincoln Memorial, where the March on Washington climaxed in Martin Luther King's 'I Have A Dream' speech
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Martin Luther King and the March on Washington
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March on Washington – 1963 Famous for Martin Luther King Jnr’s “I have a dream” speech, the march on Washington saw 300,000 people gathering at the Lincoln Memorial calling for equal rights for African-Americans
Given at the funeral of children who died in the 16th Street Baptist Church Bombing, a turning point in the civil rights movement):
"These children - unoffending, innocent, and beautiful - were the victims of one of the most vicious and tragic crimes ever perpetrated against humanity.
"And yet they died nobly. They are the martyred heroines of a holy crusade for freedom and human dignity. And so this afternoon in a real sense they have something to say to each of us in their death. They have something to say to every minister of the gospel who has remained silent behind the safe security of stained-glass windows. They have something to say to every politician who has fed his constituents with the stale bread of hatred and the spoiled meat of racism. They have something to say to a federal government that has compromised with the undemocratic practices of southern Dixiecrats and the blatant hypocrisy of right-wing northern Republicans.
"They have something to say to every Negro who has passively accepted the evil system of segregation and who has stood on the sidelines in a mighty struggle for justice. They say to each of us, black and white alike, that we must substitute courage for caution. They say to us that we must be concerned not merely about who murdered them, but about the system, the way of life, the philosophy which produced the murderers. Their death says to us that we must work passionately and unrelentingly for the realization of the American dream."
"We must realize that we are grappling with the most weighty social problem of this nation, and in grappling with such a complex problem there is no place for misguided emotionalism. We must work passionately and unrelentingly for the goal of freedom, but we must be sure that our hands are clean in the struggle. We must never struggle with falsehood, hate, or malice. We must never become bitter.
"I know how we feel sometime. There is the danger that those of us who have been forced so long to stand amid the tragic midnight of oppression - those of us who have been trampled over, those of us who have been kicked about - there is the danger that we will become bitter. But if we will become bitter and indulge in hate campaigns, the old, the new order which is emerging will be nothing but a duplication of the old order. "
"Don’t go out this morning with any illusions. Don’t go back into your homes and around Montgomery thinking that the Montgomery City Commission and that all of the forces in the leadership of the South will eventually work out this thing for Negroes, it’s going to work out; it’s going to roll in on the wheels of inevitability. If we wait for it to work itself out, it will never be worked out. Freedom only comes through persistent revolt, through persistent agitation, through persistently rising up against the system of evil. The bus protest is just the beginning.
"Buses are integrated in Montgomery, but that is just the beginning. And don’t sit down and do nothing now because the buses are integrated, because, if you stop now, we will be in the dungeons of segregation and discrimination for another hundred years, and our children and our children’s children will suffer all of the bondage that we have lived under for years. It never comes voluntarily. We’ve got to keep on keeping on in order to gain freedom. It never comes like that. It would be fortunate if the people in power had sense enough to go on and give up, but they don’t do it like that. It is not done voluntarily, but it is done through the pressure that comes about from people who are oppressed."
"I’m here to say to you this morning that some things are right and some things are wrong. Eternally so, absolutely so. It’s wrong to hate. It always has been wrong and it always will be wrong! It’s wrong in America, it’s wrong in Germany, it’s wrong in Russia, it’s wrong in China! It was wrong in 2,000 BC., and it’s wrong in 1954 AD. It always has been wrong, and it always will be wrong."