March 16 , 1869, Naperville, Illinois.
February 13, 1954, Mount Vernon, Indiana.
Horstmann was educated at Northwestern College (now North Central College), Elmhurst College, and Eden Theological Seminary. Ordained in 1931, he served churches in Indiana and Texas in his early career. He edited The Evangelical Herald of the Evangelical Synod of North America (1906-35), and was associate editor of The Messenger of the Evangelical and Reformed Church (1936-9). A number of Horstmann’s hymns appeared in The Evangelical Hymnal (St. Louis, Missouri: Eden Publishing House, 1917). His works include: