Welcome to the History Extra Podcast, fascinating historical conversations from BBC History Magazine and BBC History Review.

A hundred years ago today, on 1 September 1923, the streets of Tokyo began to shudder.

It was the first warning sign that something terrible was coming, a devastating earthquake that would level much of the city.

But, as historian Dr Christopher Harding joined me to discuss, the great canto earthquake wasn't just a natural disaster.

It also exposed deep lying social and political divides.

Thank you so much for joining me today, Chris. We're going to be talking about an event that happened exactly a hundred years ago, a devastating earthquake that rocked Tokyo.

So, what were the first signs that something was wrong on 1 September 1923?

So, this was just before midday, on that day, and from what we know, people's accounts after the event, they just started to feel the ground shaking.

I think quite lightly at first, and anyone who's ever lived in Tokyo or an earthquake prone part of the world, that's not terribly uncommon.

I lived in Tokyo for a while, and you tend to see when it first happens, you get these little rumbles and things start to shake, and people just pause to make sure that it goes away, which it generally does.

On this day, that didn't happen, so it went on five seconds and then ten seconds.

The rumbling then, this kind of side to side, got joined by the thing that nobody wants, which is this violent up and down movement, and then they know that something really serious is going on.

So, I wonder if we could go big picture for a moment before we discuss the events in more detail.

How pivotal a moment was this earthquake in the history of modern Japan?

So, for some historians, they look at this moment as a kind of reality check for Japan, especially Japan's conservatives.

So, if we think this is 1923, we are, by this point, just over 50 years into Japan's rapid modernisation, which began back in 1868.

And for conservatives in Japan, the way they read that 50-year history that's just gone by in 1923 is that it started off being really purposeful.

Everyone was pulling together in the national interest, we can perhaps talk a bit more about what that project was later on.

But then what they see or claim to see is that really perhaps from the 1910s onwards, and particularly a new generation in Japan, people always blame young people for things.

They're starting to see a loss of purpose, it's kind of everyone for themselves, their job or enjoying a consumerist lifestyle, bit of jazz, bit of cinema, some fashion.

But people have kind of lost their way, and Tokyo is really emblematic of that, especially in the minds of conservatives, because Tokyo is where all these different cosmopolitan cultures come together, different influences from America, France, etc.

The music comes in there, people are living the most as it were advanced lifestyles there.

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