Lyonsville, the oldest Congregational Church in Cook County, was organized in 1843 as the Congregational Church of Flagg Creek. Eighteen men and women – pioneers in a virtual wilderness – joined together to establish the church.  Early meetings were held in homes.  The first building built by the church members was a log schoolhouse (the first school in the area), which was used as a meeting place for the new congregation for 16 years.  The adjacent Lyonsville Cemetery was organized in 1848. The original sanctuary was built in 1858.  Ministers from Lyonsville were loaned to organize churches in Hinsdale, Western Springs, and LaGrange.  The new sanctuary was built in 1960. Lyonsville was recognized as an Illinois Sesquicentennial Church by the Illinois State Historical Society in 2010.

Lyonsville Congregational Church is a member of the United Church of Christ, formed in 1957 with the union of the Congregational Christian and the Evangelical and Reformed Churches.  Church members come from a variety of religious backgrounds.

Coming out of the Pilgrim tradition, ours is a democratic church in which the people of the church govern the church, making their decisions in the light of the gospel and out of a sense of responsibility to the whole congregation and the desire to respond faithfully to the Word of God.