Niels Henry Sonne

Niels Henry Sonne (1907–1994) was a noted librarian, a rare book curator, and expert on the Gutenberg Bible. He was born in New York City and received his bachelor's degree from Columbia University in 1930, and his doctorate in 1939.

Liberal Kentucky, originally written as Sonne's Ph.D. thesis, was published by Columbia University Press in 1939, and reprinted by the University Press of Kentucky in 1968. The book deals with the development of liberal thought in Kentucky and relates particularly to the growth of Transylvania University in Lexington, Kentucky. Sonne was employed for most of his career as a rare book librarian at the General Theological Seminary in New York City.

Gutenberg Bible
Sonne was an expert on the Gutenberg Bible's history and provenance. "A specialist on the Gutenberg Bible, Dr. [Niels H. Sonne] retired as the seminary's librarian in 1976 after 26 years." A copy held by the General Theological Seminary was studied, and found to have a forged page. An anonymous donor to the seminary gave an original page from an imperfect copy of the Bible, thus becoming the first imperfect copy of the Gutenberg Bible to be made whole again.

General Theological Seminary Library
For many years, Sonne was the head librarian of the General Theological Seminary. This library is considered America's oldest Episcopal seminary library.

He wrote several articles on the history and contributions of the library. and was a widely respected authority on the early manuscript copies of the Latin Bible and church history.

Church history
Sonne was an authority on Episcopal church history, and wrote articles on early Anglican prayer books held by the library, early American Anglican missionaries and liturgy.