Anna Gerwel always knew that her family had suffered hardships during World War II. As the daughter of political refugees from Poland who lived in Libya, Tunisia, and Italy before settling in New Jersey, when Ms. Gerwel was 14, she couldn’t help but be aware that the war played a significant role in shaping her family.

But the extent of that role became clear to her only recently. Interested in her family’s heritage, she had written to a great uncle in Poland, an engineer and amateur historian, to ask him if he could send her some family photographs or information. “I was expecting him to send me some letters, nothing out of the ordinary,” says Ms. Gerwel, who is the undergraduate administrator of Princeton University’s Department of Comparative Literature. “I was totally unprepared for what I received.”

Via e-mail, Ms. Gerwel’s uncle forwarded a yellowed copy of a letter he had received in 1977 that told of the imprisonment, torture, and death of another great uncle, Father Antoni Gerwel, at the Dachau concentration camp in 1942. According to the letter, which was written by a friend of Father Gerwel, he was among 1,700 Polish Catholic priests who were imprisoned at the notorious death camp. The friend survived his experience in the camp; Father Gerwel did not.

“I couldn’t read it very well at the beginning because the scan was difficult,” Ms. Gerwel recalls. “But after I printed it out and was able to read it, I was completely horror-stricken. This was my family. It was heartbreaking.”

The details of her uncle’s experience at Dachau were shocking. “They performed medical experiments on the priests,” Ms. Gerwel says. “They worked in the quarry and in the fields, and they were hired to plow the land. They were always beaten. They had very little to eat. They had to work out in the cold without anything to cover their heads, and their heads were shaved.”

But despite her horror, Ms. Gerwel wanted to know more. She began to do research. “Because the letter had information about hundreds of other priests imprisoned at Dachau, I started searching and found out the entire picture of 1,700 priests imprisoned there,” she says. “I emailed Dachau. I couldn’t believe it really happened. They emailed me back the confirmation and proof that he was there and he died there.”

After getting the news from the Dachau memorial site last May, Ms. Gerwel put together an account of the experiences of Polish Catholic priests at the hands of the Nazis.

“This is a story of one aspect of World War II atrocities committed against Poland, a story of Polish Catholic priests,” she wrote in her introduction. “I am focusing on this group of people because I have observed that their story is little known and therefore they have been given neither adequate respect nor recognition in light of this great human tragedy. This is not meant to be a research paper, but rather an evolving quest for the lost truth.”

She submitted the account to the Holocaust Museum in Washington, D.C., along with the original letter that had been forwarded to her by her uncle. The letter is now in the museum’s permanent collection.

Ms. Gerwel also sent copies of her account “to everybody I thought would be interested,” she says. “One professor from Washington invited me to speak, and I gave a presentation at the Institute of World Politics last November. Just speaking about it was very painful.”

As a Catholic who also has Jewish relatives, Ms. Gerwel is especially attuned to the atrocities committed against both groups. “I do believe the Jewish people suffered much worse, but Catholic Poles also suffered,” she says. “I hope that the suffering of the priests will be more known. I believe that this is important. It’s not very publicized. I was surprised to see how few people know about it. I feel people are forgetting what happened in Dachau.”

She hopes to translate her account into German and send it to institutions in Germany. “A lot of German students I speak to don’t know about it,” she says. “A couple people who are German Poles asked me why I was writing this. They said the Germans were just following orders, and the Polish priests must have been impolite to have had such treatment.”

The fact that the priests underwent medical experimentation is particularly disturbing, Ms. Gerwel says, because she comes from a medical family. “I’m passionate about shining a light on that,” she says. “I’ve been learning more and more that many physicians in Germany knew about this. They issued an apology last year for crimes against Jews and other ethnic groups, the horrors in the medical community.”

Most of all, Ms. Gerwel hopes her work will deepen understanding and keep alive the awareness of the atrocities. “I want to bring the Catholic and Jewish communities together,” she says. “That is so important to me.”