Carolltown was founded by a priest and named for the first Catholic Bishop in the United States. All of this first started out in Germany. Peter Henry Lemke was born to a protestant family and became a Lutheran Minister. When Lemke listened to a Catholic Priest say his first mass, he converted immediate to Catholicism. On his 31st birthday Father Lemke came to Pillidelphia and eventually founded St. Joseph's at Hart's Sleeping Place in 1935. He bought 395 acres in 1840 from William Vaux, also knows as Curtis Clay Tract. Father Lemke wanted to name his settlement "Gallitizin", but Father Gallitizin wouldn't allow him to do so. They both agreed on naming the town after Bishop John Carroll of Baltimore, but it wasn't until April 19, 1858 that Carrolltown got its incorporation papers. Father Lemke built his first house, a log cabin, on the hill where a monastery now stands. His second house was built at what is now Switzlers Garage.