Theodore Hornberger was a Professor of English at the University of Pennsylvania 1960-1974. He was born in Northville, Michigan on January 13, 1906. He earned B.S. (1927), M.A. (1929) and Ph.D. (1934) degrees all from the University of Michigan, where he also served as an Instructor of English, 1928-1936, and Assistant Professor of English, 1936-1937. Hornberger was also a Professor of English at the University of Texas, 1937-1946 and a Professor of English at the University of Minnesota, 1946-1960, where he was also chair of the English department, 1950-1958. Additionally, he served as a visiting lecturer at Harvard University (1938), Northwestern University (1940), Duke University (1941, 1942, and 1950), Ohio State University (1945), and the University of Brazil (1952). 

Dr. Hornberger joined the University of Pennsylvania in 1960 as a Professor of English. He served as chair of the graduate group in English, 1965-1967 and acting chair of the Department of English, 1968-1969. He was appointed John Welsh Centennial Professor of History and English Literature in 1968 and upon his retirement in 1974 became John Welsh Centennial Professor Emeritus of History and English Literature. 

He was the author of Scientific Thought in the American Colleges, 1638-1800 (1945) and many scholarly journal articles. He was editor of Mark Twain’s Letters to Will Bowen (1941), William Cullen Bryant and Isaac Henderson (1950), and Literature of the United States (1966). 

Dr. Hornberger was a member of the Modern Language Association (chair of its American literature group in 1956), the National Council of Teachers of English (chair of its College Section 1951-1952), the History of Science Society, the College English Association, the American Historical Association, the American Dialect Society, and the Colonial Society of Massachusetts. 

Theodore Hornberger died on March 14, 1975 in Minneapolis, Minnesota where he was a visiting Professor of English at the University of Minnesota. He was survived by his wife, Marian Welles Hornberger, and two daughters, Jean Alice (Mrs. Roland Cleveland) and Katharine Watson (Mrs. Allen Denenberg).