St. Mary’s Parish was established in 1859, some eighteen months before the Kansas Territory entered statehood on January 29, 1861.

The Oregon Trail passed only two miles north of what is now St. Benedict, on the ridge between Wildcat Creek and Turkey Creek. The Trail carried heavy traffic especially in the spring when the prairie grass turned green. In 1852 travelers reported an unending stream of emigrant wagon trains as far as the eye could see. All were heading west with their sights set beyond Kansas. A pioneer woman, Ledreine Berntsen, wrote in her journal (written after 1883 because she calls the town "St. Benedict" which was the name given to the Wildcat settlement on Oct. 11, 1883 when a post office was established here): "Kansas was open for settlers and many people arrived from the north and south to homestead."

Today, in 2021, the Parish consists of approximately 140 family-members. They worship in St. Mary's Church which has been called "beautiful, absolutely fantastic", "a gallery of art", "equal to the churches in Europe", "something you would expect to find in a large city and not hidden away in this valley", "A tribute to the faith of the Catholic immigrants." One hundred thirty-eight years after its construction, St. Mary's Church is still a treasure that amazes the traveler who happens upon it.

Because of its historical, cultural, artistic, and religious significance, St. Mary's Church was listed on the Kansas Register of Historic Places in 1977 and on the National Register of Historic Places in 1980.