The following description of the history of the Old can be found in Damaine Vonada's wonderful guide book Notre Dame The Official Campus Guide (available in the "Books" section)
From The Notre Dame Campus Guide:
In 1842, when Father Sorin and his band of Holy Cross brothers first arrived at the mission site that they would transform into a university, they found a small log cabin near St. Mary's Lake. It had been built a decade before and used as a chapel by Rev. Stephen Badin, an indefatigable frontier priest who resumed the missionary work that Father Claude Allouez, the Potawatomi's first "Black Robe," began near South Bend in the late 1600s. Father Sorin and his companions lived on the first floor of the cabin, and they put their chapel in its small attic. Until they could build more adequate structures, that rude cabin was the University of Notre Dame.
The Log Chapel that you see today is not the cabin Badin built, but a replica. The original cabin burned down in 1856, and this copy was constructed 50 years later. Erected very close to the original's site, it serves as a rustic, but meaningful reminder of both Notre Dame's humble roots and the hardships faced by the missionaries who labored there. The plans for the Log Chapel were based on the memories of elderly Holy Cross brothers who had actually lived or worshipped in the Badin cabin, and it was constructed by William Arnett of Kentucky, a former slave who knew how to hand hew logs with a broadax. Father Badin is now entombed under the floor of the Log Chapel. Although he died and was originally buried in Cincinnati, he had often told Father Sorin that he wanted to be laid to rest at Notre Dame. After his cabin was reconstructed, Badin's remains were moved in order to finally grant his wish. Three other missionary priests are also interred beneath the Log Chapel: Francois Cointet, a classmate of Father Sorin's who died during the cholera epidemic that ravaged Notre Dame in the 1850s; Benjamin Petit, who passed away after accompanying the Potawaromis when they were forced to move to a reservation in Kansas; and the overworked Louis DeSeille, who died in Badin's original cabin. The young priest's final hours are depicted in The Last Communion of Fr. Louis DeSeille, a painting by Notre Dame artist John Worden that hangs near the Log Chapel's tabernacle.
The simple interior of the Log Chapel is also enhanced by a painting of the Madonna and Child by Notre Dame's first artist-in-residence, Luigi Gregori. Its altar, which is made of cherry planks fastened by wooden pegs, came from a mission that Father Sorin started in nearby Bertrand, Michigan, for the Sisters of Holy Cross. Displayed in the sacristy are numerous items that belonged to several early priests and missionaries, including the vestments of Father Jacques Marquette, who accompanied the seventeenth-century explorer Louis Joliet. Although the Log Chapel is quite small, its enormous symbolic significance in Notre Dame's development makes it a popular site for weddings and baptisms, and you'll often see beaming parents and godparents bringing infants there. Also used for mass, prayer meetings, saying the rosary, and special events, the Log Chapel is usually open to the public on graduation and home football game weekends.
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