During his speech in Pennsylvania on Monday, President Joe Biden shared a somber story about his great-grandfather, who was wrongly accused of murder—a tale he emphasized was “not a joke” to the Pittsburgh audience.

For about 90 seconds, the crowd, holding signs, listened in silence as the 81-year-old president recounted an episode from the 1906 election when his great-grandfather, Edward Francis Blewitt, ran for statewide office.

Biden highlighted that Blewitt was “only the second Catholic” to achieve such a position. According to Biden, his ancestor was accused of being a “Molly Maguire,” a term used at the time to describe Irishmen alleged to have committed violent acts against abusive coal mine foremen.

The story was part of Biden’s Labor Day speech, aimed at winning over steelworkers in the battleground state, who are crucial voters for Vice President Kamala Harris.

“A Molly Maguire back in the – in the old days, when we Irish and the Catholic and the Poles and others that were Catholic – when they came to the United States of America in the beginning of the 1840s, late 1840s, made their way down into Pennsylvania,” Biden rambled.

“A lot of them – and there’s, there’s a tier in the coal mines. Those guys who got there last ended up being the last people in the coal mines. But a lot of the English owned the coal mines,” Biden recalled as audience members glanced to one another, hoping for a point to the story.

“And what they did was, they’d really beat the hell out of the, uh, the mostly Catholic population that was in the mines. Not a joke. Not a joke,” he added.

According to Biden, his great-grandfather was a principled politician advocating for the rights of immigrant laborers during a time of widespread exploitation. The advocacy triggered a smear campaign by mine owners who sought to undermine Blewitt’s efforts to support the Irish workers and prevent him from succeeding in the Pennsylvania State Senate, according to the president.

“But there was a group called the Molly Maguires, and the Molly Maguires, they’d find out the foreman who was taking advantage of an individual, and they’d literally kill him,” he went on, prompting gasps from the audience. “Not a joke,” he repeated, “and they’d bring his body up and put his body on the doorstep of his family. Kind of crude. But I’ve gotta admit: They accused my great-grandfather of being a Molly – he wasn’t.”

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