St. John's Military Academy (SJMA) was founded in 1884 by 22-year-old Rev. Sidney Smythe, a student at nearby Nashotah House.
In 1859, Dr. James DeKoven, rector of St. John Chrysostom Church in Delafield, had opened a preparatory school for men aspiring to attend the Episcopalian seminary, but it closed that same year when DeKoven was transferred to Racine College.
Smythe reopened the abandoned schoolhouse 25 years later to provide young men with physical, moral, and religious education. Even today, the school motto is "Work Hard, Play Hard, Pray Hard."
The school grew quickly, and four large buildings were added by 1894: Armitage Hall, DeKoven Hall, Kemper Hall (seen here), and Memorial Hall - the only one that still stands today.
Campus buildings were constructed in the English Gothic style, resembling European castles, and built to complement each other.
Kemper Hall was designed by John A. Moller of Milwaukee and completed in 1894. It was named in honor of Rev. Lewis Ashurst Kemper, an 1852 graduate of Nashotah House and professor of Exegesis, Biblical Literature and Hebrew who taught Rev. Smythe.
Over the years, the building served as a chapel, classrooms, and cadet rooms until it was razed in 1975. In 1977, SJMA was added to the National Register of Historic Places.
In 1994, SJMA merged with Northwestern Military & Naval Academy of Highland Park, Illinois, and changed its name to St. John's Northwestern Military Academy.