Schaff–Herzog Encyclopedia of Religious Knowledge

It is based on an earlier German encyclopedia, the Realencyklopädie für protestantische Theologie und Kirche.

Like the Realencyklopädie, it focuses on Christianity from a primarily Protestant point of view.

The new Schaff-Herzog encyclopedia of religious knowledge, embracing Biblical, historical, doctrinal, and practical theology and Biblical, theological, and ecclesiastical biography from the earliest times to the present day.

The idea of translating Herzog in a slightly condensed form occurred to John Henry Augustus Bomberger, a minister of the German Reformed Church, and then president of Ursinus College, Collegeville, Pennsylvania, and in 1856 he brought out in Philadelphia the first volume, whose title-page reads thus: The Protestant Theological and Ecclesiastical Encyclopedia: Being a Condensed Translation of Herzog's Real Encyclopedia.

But the American Civil War breaking out the next year put a stop to so costly an enterprise and it was never resumed.

[1] In 1877 Professor Philip Schaff (1819–93) was asked by Dr. Herzog himself to undertake an English reproduction of the second edition of his encyclopedia, and this work was fairly begun when, in the autumn of 1880, Clemens Petersen and Samuel Macauley Jackson were engaged to work daily on it in Dr. Schaff's study in the Bible House, New York City.

David Schley Schaff, later professor of church history in the Western Theological Seminary, Allegheny, Pa., joined the staff.

The title-page read thus: A Religious Encyclopædia: or Dictionary of Biblical, Historical, Doctrinal, and Practical Theology.

Edited by Philip Schaff, D.D., LL.D., Professor in the Union Theological Seminary, New York.

In November, 1886, a revised edition was issued and at the same time the Encyclopedia of Living Divines and Christian Workers of All Denominations in Europe and America, Being a Supplement to Schaff-Herzog Encyclopedia of Religious Knowledge.

George William Gilmore, bringing the biographical and literary notices down to December, 1890.

But inasmuch as there was a space of ten years between the beginnings of the two works, it has been necessary to bring the matter from the German down to date.

This end has been accomplished by two courses: first by securing from the German contributors to Herzog condensations of their contributions, in which way matter contributed to the German work has in many instances been brought down to date, and second by calling on department editors for supplementary matter.

A set of The New Schaff-Herzog Encyclopedia of Religious Knowledge.
The German Realenzyklopädie für protestantische Theologie und Kirche, which Schaff-Herzog is based on.