The parish’s first church was financed partly through the efforts of Henry Hart of Ireland, who came to Douglas County in 1880, to visit his nephew, William Dillon. Hart saw the need for a church, and Adeloide Hart of Ireland, William’s mother, left money as a nucleus for a building fund. The family’s one request was that the church be named St. Francis of Assisi in honor of William’s brother, who was a Franciscan priest.
By 1887, pledges amounting to $500, some from non-Catholics, had been collected. It was decided that the church would be built of rhyolite stone from the local quarries. The carpenters’ names are unknown although stories tell of donated labor. In December 1888, the Castle Rock Journal reported: “The dedication of the new Catholic church took place last Sabbath (Dec. 16, 1888). Quite a large congregation was in attendance. The church having been blessed and dedicated, a collection was then taken up and $27.50 realized, the whole of which sum was handed to Mr. Dillon to assist paying off the small debt still remaining on the church.”
In 1966, the parish relocated to the present location on Fifth Street and the original church building is now a restaurant on The Square. St. Francis of Assisi serves the needs of Catholics in Castle Rock, Sedalia, Larkspur, Franktown and other surrounding communities. On October 4, 2011, the Feast of St. Francis of Assisi, a newly completed sanctuary was dedicated which now seats over 800 parishioners.