J.V. B. Flack is considered to be one of the founders, if not the founder, of Excelsior Springs. He traveled here in 1880 when word of the curative powers of a spring water reached him at his Missouri City home. After investigating the reports of the water, he advised the owner of the spring, A.W. Wyman, to have the land platted, the water analyzed and to begin advertising the cures of the water. Flack built a home on the 40-acre tract that Wyman had platted and opened the first dry goods store, as well as founding the first church. From Longfellow's much quoted poem, he named the spring "Excelsior", later changed to Siloam. Finally becoming part proprietor, he undertook the management of the new enterprise.

The side-steeple brick church is Gothic Revival in style. In 1912, money was collected for the building as the congregation had outgrown the first one. According to the introduction of "Life History of J.V.B. Flack, D.D.", the autobiography provided by Flack's wife, Marietta, was printed and sold, with all proceeds to help build the church as a memorial. When it was replaced in 1913, the Rev. Tom Martin was pastor. It was dedicated in June 1913 with the Rev. A. C. Thomas officiating.