In 1883, the first bishop of Helena, John Baptist Brondel, proposed a Catholic college in Montana to help produce future priests for the soon-to-be diocese of Helena. He died before his plans could be realized. Pope Pius X selected John Patrick Carroll, a young priest from Dubuque, Iowa, as Brondel's successor.

Bishop John Patrick Carroll, second Bishop of the Diocese of Helena, was able to carve out the funding needed to launch the college while at the same time raising money to construct the Cathedral of St. Helena. In 1909, William Howard Taft, 27th President of the United States, helped lay the cornerstone of St. Charles Hall at the college.

The college was founded on September 27, 1909, by John Patrick Carroll, second Bishop of the Diocese of Helena, Montana. It was originally called Mount St. Charles College to honor St. Charles Borromeo. The intent was for it to be an all-men's liberal arts college, with an emphasis on preparing men for careers in the priesthood, law, medicine, teaching, and engineering. In his speech after laying the cornerstone of St. Charles Hall, President William Howard Taft said, "The college you are building here will be a blessing to Helena and to the whole state of Montana. The only trouble is we do not have enough institutions of this kind in the United States."

In September 1910, Mount Saint Charles College opened its doors for classes. The first college student graduated in 1916. In 1932, the school's name was changed to Carroll College in honor of its founder.

During the 1935 Helena earthquake, Carroll College suffered only minor damage, while many other buildings and schools in the city were greatly affected. Property damage was estimated at half a million dollars. The top of the gable wall on the southern portion of St. Charles Hall was damaged and many of the structure's large stones had fallen off. The college decided to replace the roof with a slightly shorter and flatter roof.

The fallen stones were repurposed and used to build an observatory on campus. Carroll College's Neuman Observatory, named after former chemistry professor Edward Neuman, is the oldest astronomical observatory in the state of Montana.

During World War II, Carroll College was one of 131 colleges and universities nationally that took part in the V-12 Navy College Training Program; it offered students a path to a Navy commission. After the war, the college began a period of expansion that included enrolling many military veterans under the GI Bill. It later admitted the first female students and was transformed by changes resulting from the Second Vatican Council.

The 1989 Helena train wreck caused significant damage to Carroll, notably to Guadalupe Hall, the women's dormitory at the time.

In addition to providing lodging and education to the students who put in significant effort to attend this Catholic college, this location is also home to several other ghostly entities, both visible and invisible. People say these spirits roam the halls, sharing their stories with those who sense their presence. Some students claim to have encountered fleeting shadows and whispered voices, adding an air of mystery to their academic pursuits.

The room on the fourth floor of St. Charles Hall has been locked because there are recurring bloodstains in the sink, and there has been an appearance of an apparition of the student who died after hitting his head on the sink. All those still alive witness a reenactment of a student who committed suicide by jumping from the stairway. The chilling atmosphere deepened each time someone recounted the tales of those lost, as if the very walls of the hall absorbed their sorrow. Fear rippled through the students, prompting them to steer clear of the hall. Yet, curiosity gnawed at the edges of their minds, drawing some to the threshold, where shadows danced ominously in the flickering light.

In the hallways of the student union on the top level of St. Albert's Hall, many who are still alive have reported seeing a nun appear and disappear throughout the building. Because of her illness, she passed away in this building. People said her presence lingered, acting as a spectral guardian of the memories stored within those walls. Whispers of her story circulated among the students, blending fear with fascination, as they dared each other to venture closer to the haunted hall.