If you take a stroll around Princeton University, in the state of New Jersey, you'll find an idyllic campus with majestic buildings and elegant trees. The charming surroundings long disguised more chilling parts of the university's past.

In the Princeton and Slavery Project, the university has dug deep into its own history: uncovering racial violence on campus, the fact that its first nine presidents had slaves, and that people were sold into slavery at an open auction on campus. The historian Martha Sandweiss started the project.

DW: How did you come up with the Princeton and Slavery Project?

Martha Sandweiss: When I moved to Princeton in 2009, I was really ignorant. I had heard that it was the most southern of the Ivy League schools, but I didn't really know what that meant. I learned that nobody here was really investigating these important questions about institutional connections to slavery. Our university was founded in 1746, so I was quite certain I would find a story there as almost all 18th century institutions in what's now the United States were tied in some way or another to slavery.

So in spring of 2013, I taught a small undergraduate research seminar, not having any big project in mind - I was just curious what we could we find in the archives. Over the years it's grown to be a really ambitious project. On the project's website we have the equivalent of more than 800 printed pages of researched stories and 370 primary sources. In the first week the website was up, people viewed it from 95 countries. The feedback has been so gratifying.

What are the most significant findings that you and your team made?

MS: One finding was that we are very much like other universities. It's not shocking that our early trustees owned slaves, that our faculty members and first nine presidents owned slaves. We would find the same story at Harvard or Yale. In a way it's not shocking that on our campus, liberty and slavery are so closely intertwined: the Continental Congress met on our campus, but free people were also sold on our campus in a public slave auction. That's the paradox at the heart of all of American history.

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The thing we found that makes us different is how "southern" we were at the university. When our peer universities Harvard and Yale had maybe 9 or 10 percent of their students coming from the south, we had an average 40 percent, and this had lots of consequences on campus. It helps to explain acts of violence in the 1830s and 40s and 50s when boys from slaveholding southern families, who had never seen black people before, encountered them on the streets of our town. It didn't always go so well.

It explains why such a conservative political ethos evolved on our campus: we depended on the tuition money from the southern families and had to assure parents that this was not a radical school, that we wouldn't challenge their families' beliefs, that their boys would be safe here. Abolitionists were not really welcome on our campus, whereas southern boys were made to feel very welcome. That makes us different.

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Are there any specific personal stories you've researched that stunned you in particular? 

MS: We found some amazing people. One of my favorite stories concerns a woman named Betsey Stockton. She was enslaved and owned by Ashbel Green, one of the presidents of our university. But she learned to read and write in his household on our campus. He freed her in 1817 and she became the first African-American woman to be a Christian missionary in Hawaii. She later came back and was an educator at a segregated school in our town for about 30 years. So she went from slavery to being an educator. Extraordinary.

There's another story of a man, James Johnson, who ran away from slavery in Maryland, got as far as New Jersey, presented himself as a free man and got a job on campus. Then, with a twist only a perverse novelist would make up, he was recognized by a student who had grown up on a neighboring farm in Maryland. He was put on trial as a fugitive slave.

You know, these stories are just extraordinary. They're right here, encoded in the DNA of our campus. I hope now that this project is out everyone will know them.

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Why is this such an important project and why is it just happening now?

MS: I think historians have been saying this for a long time that America is long overdue for a real reckoning with its own historical past, in particular with the historical legacy of slavery. Historians have been uncovering these stories, but there just hasn't always been an easy way for people to receive them and to share them. Now, people begin to realize the problem of race is still front and center in our country and to wonder "Gosh where did that come from?"

My hope is that whatever conversations ensue on our campus, or in our town, are going to be deeply informed. Historians don't know the future; they're better at talking about the past, but I'll take a leap and predict that the conversations in this community will be all the more powerful because we have given people so much information to wrestle with.