This is America in Pursuit, a limited run series from ThruLine and NPR.

I'm Randaab del Fet d'Achtar.

Each week, we bring you stories about life, liberty, and the pursuit of happiness in the U.S. that began 250 years ago.

You could probably sum up the entire history of the United States

with the idea of people pushing to make a change.

Where that change happens is a whole other story.

Sometimes it's on the battlefield, in the courthouse, or in the city streets.

Other times, it's in a stadium, on a field, or in the ring.

It's December 26th, 1908, and World's heavyweight champion Tommy Burns

defends his title in Sydney, Australia, against Jack Johnson.

Jack Johnson is determined to become the first black heavyweight champion.

Johnson has been after this heavyweight title fight for over two years.

As Jack Johnson enters the ring, he's already making history.

Up until this fight, it was a known, although unspoken rule.

That no black fighter would be allowed to fight for a championship, particularly in the heavyweight division.

When the fight begins, the mood is tense.

There's a lot more at stake than just the title.

Sports have long been a place where people challenge the status quo.

From Jackie Robinson, breaking segregation lines in the MLB,

to athletes in the 1960s and 70s, like Muhammad Ali or Tommy Smith and John Carlos,

championing black power and civil rights,

to Colin Kaepernick in 2016, taking a need during the national anthem against racism and police brutality in the U.S.

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