Uncovering the Underground Railroad to Mexico

Details: Historians have known for decades that some enslaved Black people in Texas, Louisiana, Oklahoma and Alabama escaped slavery by heading south.

• Oral histories, archives of slave escape ads, and narratives of formerly enslaved people show that fleeing to Mexico had been a possibility leading up to the U.S. Civil War.
• Abolitionists wrote about "colonies" of formerly enslaved Black people popping up in towns across northern Mexico — a country that had abolished slavery in the 1830s.

Yes, but: How many people fled south of the border remained a mystery, and historians debate just how well-organized the network was.

The intrigue: New research shows that between 4,000 to 10,000 enslaved Black people may have taken the trek south, Alice Baumgartner, author of "South to Freedom: Runaway Slaves to Mexico and the Road to the Civil War," told Axios.

• That's small compared to the Underground Railroad of the north where 30,000 to more than 100,000 may have braved that more famous journey, said Baumgartner, a history professor at the University of Southern California.
• Historians also are combing through Spanish-language material discussing the arrival of enslaved people and how they would integrate into Mexican society, giving clues to what happened to those who escaped.

How it worked: Enslaved people would leave farms and head south with the help of poor Mexican Americans, German immigrants and abolitionists who hid them in places from East Texas to isolated regions approaching the Rio Grande.

• Biracial Black and white couples living along the Rio Grande hid escapees until they could take ferries into Mexico, where they would change their names and marry.
• Scholar María Esther Hammack's research into one formerly enslaved woman, Silvia Hector Webber, showed how she assisted runaways along the border.
• Baumgartner founded cases of enslaved people hiding on ships docked in New Orleans heading to Mexico, where laws granted enslaved people immediate freedom.

But, but, but: Texas slaveholders organized posses to invade Mexico in attempts to recapture their "property."

• The white-led mobs faced resistance from Mexico as violence erupted.
• "I was shocked at how many documents I came across that had to do with kidnappers from the United States, arriving to try to kidnap enslaved people who had escaped to Mexico," Baumgartner said.

• "They faced resistance from the enslaved people themselves, but also from Mexican citizens."
• Those mobs in Mexico also saw armed resistance from Black Seminoles — or Los Mascogos — who had resettled in northern Mexico.

What's next: The U.S. National Park Service is looking into expanding its Underground Railroad route from Natchitoches, La., through Texas to Monclova, Mexico, which is considered a rough path of the southern-bound Underground Railroad.

• Last year, the agency convened scholars like Roseann Bacha-Garza, a program manager for the University of Texas Rio Grande Valley’s Community Historical Archaeology Project with Schools in Edinburg, Texas, to present new research.
• Bacha-Garza said she recently participated in a documentary examining the Underground Railroad to Mexico.
• "This is a very important part of American history, and we are constantly on unearthing new information."

One fun fact: Relationships created in Mexico convinced some emancipated Black people to travel south over the border after the U.S. Civil War.

• William Ellis, a formerly enslaved man in Texas, later became a millionaire in Mexico.

Editor's note: The story originally published on Feb. 7.

Go deeper: Story of the Underground Railroad to Mexico gains attention (via AP)

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