The Speeches That Shaped History And Why They Still Influence Audiences Today

Some speeches are more powerful than others. Some of the most famous speeches that changed history have stuck not only with the people who were there in-person to witness them, but they have become powerful historical moments. I’m sure you can all recount the quote “I have a dream” – even if you weren’t in the audience, or even born back when that speech was delivered!

I’ve been lucky enough in my role at The Speakers Agency to witness audiences ‘changed’ by certain speeches. One particular moment that sticks with me is watching Baroness Floella Benjamin deliver a talk to my client in 2024. Hearing her share her journey as part of the Windrush generation and the racial abuse she received as a child was so moving. She received a standing ovation and there wasn’t a dry eye in the room. 

So how do we define these certain speeches that echo across decades, shape movements, shift beliefs and remind us of what human communication can achieve at its very best?

As a speaker bureau, we spend every day immersed in talks, ideas and the craft of speeches. What fascinates us as a team is not just what iconic speakers throughout history have said, but why their delivery still teaches us so much about connecting with an audience in 2025 and beyond.

Martin Luther King Jr. – “I Have a Dream” (1963)

Perhaps the most famous speech of all time. It’s taught in schools across the globe. So, why is it so special? MLK didn’t just describe a dream, he actually painted one for the people he was speaking to. His use of vivid imagery, rhythm and gradually escalating momentum remains a masterclass in how to deliver a message that feels musical, memorable and magnetic.

He repeats the opening stem “I have a dream”, and invites listeners into a shared vision of what humanity could look like at its best. His message is delivered with a confidence that is not in volume, but in the purpose of what he says.

If you haven’t already seen this speech, I urge you to watch it here (although I’m sure you already have!)

Winston Churchill – “We Shall Fight on the Beaches” (1940)

Although a controversial figure, Winston Churchill’s impact in his “We Shall Fight on the Beaches” speech is undeniable and is definitely one of the most famous speeches that changed history

Addressing a tricky subject matter, Churchill didn’t soften the harsh reality of wartime Britain. Instead, he acknowledged it clearly, then anchored his listeners in how they could be resilient. His signature repetition (“we shall fight…”) created rhythm, urgency and unity.

Lots of our modern speakers still borrow this format when rallying teams through uncertainty. It’s a reminder that when stakes are high, honesty paired with confidence is far more powerful than sugar-coating problems. 

Nelson Mandela – “I Am Prepared to Die” (1964)

Mandela’s speech, delivered during the Rivonia Trial, is one of the most powerful examples of conviction under pressure. He wasn’t speaking to save himself; in fact, he says the opposite. Mandela was speaking to advance a cause greater than himself. 

This speech is the epitome of moral groundedness. He shows that great speaking isn’t always loud. Often it’s actually the quietest voice in the room that carries the most weight.

We have many speakers who show this same moral groundedness. Founder of Black Pride Lady Phyll Opoku-Gyimah, Nova Reid, Professor Nicola Rollock; they all too advocate for this “harmony and equal opportunities” for which Nelson Madela was prepared to sacrifice his life. 

Jacinda Ardern – Christchurch Address (2019)

In 2019, on a standard Friday lunchtime, people gathered for prayers at a mosque in Christchurch, New Zealand. Out of nowhere, a young man walked up to the door brandishing an assault rifle and took the lives of 50 people in a place of worship. New Zealand’s PM Jacinda Ardern handled this in a way that garnered her praise across the world. 

She really showed what empathetic, respectful leadership communication can look like. 

The most famous line from this speech was “They are us.” Ardren reframed national identity in just three words. It was perhaps the most unifying thing she could have said. 

There’s often a misconception that leaders are expected to be forceful. Ardern demonstrated that empathy can be one of the most powerful tools a communicator has.

Greta Thunberg – UN Climate Action Speech (2019)

If I said the words “How dare you?”, there’s probably only one name that springs to mind. 

As well as the impact of her age, Greta Thunberg’s impact came from rawness. When speaking to her audience it was a challenge, a plea and a disruption.

What These Speeches Teach Us About Communication Today

Whether spoken in 1940 or 2019, each of these speeches moved people because they share timeless qualities:

• clarity
  
• emotional resonance
  
• rhythm and structure
  
• vulnerability
  
• purpose rooted in lived experience
  

The technology around us may change – from AR keynotes to AI co-writers – but human communication still hinges on the same fundamentals as it did hundreds of years ago. 

As a speaker bureau, we see these traits reflected in the speakers who transform rooms: the ones whose message lingers long after the event ends.

Why Great Speeches Will Always Matter

Even as AI advances and new formats emerge, these iconic speeches that changed history remind us of something profound: communication at its best is deeply, beautifully human.

Great speaking isn’t about perfect language or being the most forceful person in the room, it’s actually about shared emotion.

That’s something no algorithm or avatar can replicate.