This collection documents the life and work of Mahlon Van Horne, who served as pastor of the Union Congregational Church in Newport, Rhode Island, for 28 years, beginning in 1869, along with papers from his family. Included is the original manuscript of his sermon, “The Negro in Rhode Island,” that he delivered in 1887, a letter he wrote October 15, 1902, reporting the death of his son in a horse-riding accident in St. Thomas, a letter addressed to Florence (Van Horne) Miller, a collection of photographs of Van Horne, his family, and locations in Newport and St. Thomas, a wedding certificate from his marriage to Rachel Ann Huston in 1862, a certificate of confirmation of his son, Mathias Alonzo, dated April 10, 1898, and a bill for the funeral services of his wife dated January 6, 1902.