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This is 99% Invisible. I'm Roman Mars.

Salut, Tom. Kirvi Fattas.

Let me start with this. The invented language of Esperanto has a flag, and it kicks ass.

Green field, white canton in the upper left corner with a green 5-pointed star on it.

I'd be on board because of the design of the flag alone.

Seriously, I could march in the streets behind that flag, but that's not the Esperanto way at all.

Esperanto is about hope.

It was created in the 1880s by a Polish eye doctor named Ludwig Saminhof.

He lived in this town, Biola Stock, where there were Poles, Jews, Germans, and Russians.

They all spoke different languages, and they all hated each other.

He had this idea that if everybody spoke a common language, they could communicate, they could get to know each other as people.

There wouldn't be any more racism or conflict, which is a beautiful idea.

This is Sam Green.

My name is Sam Green. I'm the director of Utopia in the Four Movements.

One of the four movements of Sam Green's live documentary is about Saminhof's Utopia of Esperanto.

In some ways, the history of Esperanto really mirrors the 20th century in a certain flowering of Utopian energy and ultimate waning of that by the end of the century.

Saminhof's full dream of peace through a shared second language never came to pass.

According to estimates, somewhere between 50,000 and 2 million people speak Esperanto.

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