Alan Taylor, his new book is American Civil Wars of Continental History.

Harriet Tubman, she escapes slavery and travels to Canada, but then risks her life again and

again coming back.

What did she see that she could achieve?

We call it the Underground Railroad.

How did it work, Professor?

Well, the primary conductors of this railroad, the railroad is not institutionalized, it's very informal.

But there were networks of people, mostly free African Americans living in northern

states, but also a significant number of sympathetic white northerners,

especially Quakers.

And they would hide out enslaved people who were running away from slavery in Maryland, in Tubman's case, Virginia, Kentucky.

So it's important to bear in mind that while Northern States had freed

themselves of slavery in their midst, they remained within the United States and under the law of the United States

under the law of the US Constitution the original Constitution. There was a future slave clause that bound all states within the union to return what was called runaway

property. So if you escape from slavery in Maryland and you made your way to Pennsylvania, you are not fully free because

there was always the danger that some constable or some posse or slave catchers would come and grab you and take you before a magistrate

and it would be ruled that you were a form of property back in the state of Maryland and take you back there.

So for any kind of security in this new freedom of the runaway, the runaway would have to make

it all the way to Canada.

And that's what Harriet Tubman did but she still had

friends and family back in Maryland and so she did her best to slip back into

Maryland and to arrange the escapes and she knew the sympathetic people along the way

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