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

Today, California is renowned worldwide as a heartland of sun-drenched luxury.

But according to a new book by Jean Felser, the state's prosperity is in large part built on the proceeds of human bondage.

I spoke to Jean about the various forms that slavery has taken in the state down the centuries.

From Native Americans forced into indentured labour to Chinese girls trafficked into cage brothels.

Thank you so much for joining me, Jean.

You say in the introduction to your book that, quote, the story of California is a history of 250 years of uninterrupted human bondage.

What forms has that bondage taken?

I turn to Frederick Douglass, the great American abolitionist.

Douglass says that slavery is a hydra, and if you cut off one head, two heads grow in its place.

And this hydra, this serpent slithered across California's history, and it created a series of forms of slavery, really depending on power,

who was in power, who was running California, who owned California at the time.

California has this free-spirited aura, but in fact it was a colony.

And it was a colony first of Spain, then a colony of Russia, then a colony in Mexico, and then in my view, a colony of the United States.

And it absorbed, like a sponge, the various forms of slavery that were being evolved in each of these places.

And I think it's important to say at the start of this conversation how you define slavery.

So we're not just talking here about the transatlantic slave trade and plantation slavery.

We're talking about indentured labour and sex trafficking. Could you give us your definition of slavery?

Slavery in California was very unique, but it also has a lot of overlays with global slavery and the way slavery evolved in the British colonies and in the South in the United States.

And then how it spread into the North in the United States, I think people are coming to understand more and more that it wasn't contained.

It wasn't boxed in in the South, it leaked, and as it leaked, it morphed into these different forms.

Let's start with the commonalities. Slavery is always violent. It is always violent.

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