Major funding for backstory is provided by an anonymous donor, the National Endowment for the Humanities, and the Joseph and Robert Cornell Memorial Foundation.

From Virginia Humanities, this is backstory.

Welcome to backstory, the show that explains the history behind today's headlines. I'm Nathan Connolly, and I'm Brian Ballot.

If you're new to the podcast, we're all historians, along with our colleagues, Ed Ayers, and Joanne Freeman. And each week, we explore a topic in American history.

Last month, youth climate activists Greta Tunberg gave an impassioned speech at the United Nations Climate Summit. During the speech, she admonished world leaders for their unwillingness to take meaningful action against climate change.

You have stolen my dreams and my childhood with your empty words. People are suffering. People are dying. And tired ecosystems are collapsing. We are in the beginning of a mass extinction. And all you can talk about is money and fairytales of eternal economic growth. How dare you?

But this is hardly the first time the world has faced the prospect of mass extinction. In the beginning of the 20th century, America's flora and fauna were seriously threatened by urban encroachment and overhunting. And one animal at the center of this struggle was the bison.

By the end of the 19th century, once various environmental factors and human hunters had done their work, there were fewer than a thousand bison left in North America.

That's Andrew Eisenberg. He specializes in environmental history and has studied how the bison went from an animal in excess to near extinction in the 19th century. He says at one point in the early 1800s, there were tens of millions of bison roaming America's great planes.

Some years it may have been above 30 million and then they may have overgrazed the range and then the number would crash. The number of bison is always fluctuating and going up and down. That 30 million or 24 or 25 million is probably much closer to the maximum number that the great planes could sustain.

So how did an animal which graze the western grasslands and its millions, which the brink of extinction in under 100 years? And what's the current state of the bison?

Today you can find bison protected on animal preserves in the west and package for consumption on the shelves of grocery stores.

And in 2016, President Obama named the bison America's first national mammal. So what exactly does the animal represent to people? And how is the bison population changed with the times?

In celebration of World Animal Day, we're going to explore the history of the bison in the United States. We'll hear more from Andrew Eisenberg on what caused the bison's destruction in the 19th century. And why some today see it as a symbol of a bygone American frontier.

You'll find out how windman is working to restore Buffalo for the eastern Shoshone tribe at Wind River Reservation in Wyoming.

And you'll learn about the surprising and troubling connection between bison preservation and Adolf Hitler.

Let's start our story back in the early 1800s when millions of bison roamed the great planes. And as Andrew Eisenberg says,

diverse groups of Native Americans like the Lakota and Cheyenne tribes were hunting them.

If you look at the number of natives and you look at the pressure they're putting on the bison in a good year, the number of bison that they're consuming for food and for hides for their lodges and for robes, keep themselves warm.

The robe is the winter skin of the bison with the hair still attached. All of that was well within the capacity of the bison to sustain.

But in the 1860s everything changed with the influx of white hunters in the great planes.

In a short amount of time, Eisenberg says these hunters delivered a devastating blow to the bison population.

...