Theophil Henry Hildebrandt was born July 24,1888 in Canal Dover, Ohio. His parents, German nationals (although his mother had been born in West Africa), were Basel missionaries in Africa. Following their marriage, they left the mission field and immigrated to the United States.
After the birth of Theophil, the Hildebrandt family moved from Ohio to Bellewood, Illinois. Young "T.H." Hildebrandt was something of a prodigy. After completing high school in three years, he entered the University of Illinois at the age of fourteen, earning his B.A. degree in mathematics in 1905. He received both an M.S. (1906) and a PhD (1910) from the University of Chicago before he turned twenty-one.
In 1909 Hildebrandt came to Ann Arbor as an instructor in mathematics. His rise in the department was steady. He was an assistant professor by 1914, an associate in 1920, and became a full professor in 1923. Hildebrandt was appointed chairman of the department of mathematics in 1934, and he retained this position until he retired in 1957. He was also the supervisor for research projects in pure mathematics sponsored by the Office of Naval Research.
Hildebrandt's interests in mathematics included the theories of integration, integral equations and linear spaces. He published one textbook Introduction to the Theory of Integration (New York and London; Academic Press, 1963), and wrote numerous articles and reviews.
Hildebrandt won the Chauvenet Prize for an outstanding article in 1929. In addition, he was an elected member of Phi Beta Kappa, Sigma Xi (President of the Michigan Chapter), and Phi Kappa Phi. In 1963, the University of Michigan created the "T.H. Hildebrandt Research Instructorships" for young mathematicians. These were later changed to assistant professorships in 1974.
Other affiliations of his included the American Association for the Advancement of Science (vice-president, 1935), the American Mathematical Society (vice-president, 1924-1926), the Mathematics Association of America (vice-president, 1937), the National Research Council, the National Council of Mathematics Teachers, and the Societe' Mathematique de France. From 1938 to 1942, Hildebrandt was an editor for the American Journal of Mathematics. He was also a president of the University of Michigan Research Club, and before his marriage (to Dora Ware, 1921), he was a member of the Apostles, a University club consisting of no more than twelve unmarried faculty men. He was also a member of the Pleasant Lakes Club.
In addition to mathematics Hildebrandt had a life-long passion for music. Shortly after becoming an instructor in 1909, he enrolled in the University of Michigan School of Music. In 1913 he received a B.A. in organ performance. From 1913 to 1917 he was the organist and choir director of the First Congregational Church of Ann Arbor. As a result of anti- German sentiment expressed toward him by this church during the First World War, Hildebrandt left and became the organist for the Bethlehem United Church of Christ, also in Ann Arbor.
Even after Hildebrandt retired from the University of Michigan in 1957, he continued to teach one year stints at other universities, and maintained an active interest in mathematics until he was quite old. He died October 9,1980 at the age of ninety-two.
From the guide to the Theophil Henry Hildebrandt Papers, 1887-1978, 1930-1960, (Bentley Historical Library University of Michigan)
