Philip Schaff, an American scholar, born in Coire, Switzerland, Jan. 1, 1819. He studied at Tubingen and Halle, graduated at Berlin in 1841, travelled as a private tutor, and lectured on theology in Berlin in 1842. Being invited to the chair of theology at Mercersburg, Pa., he was ordained at Elberfeld, and came to America in 1844. In 1845 he was tried for heresy and acquitted, and afterward continued to teach and write at Mercersburg, in connection successively with Dr. Nevin and Dr. Wolff. In 1854 he lectured in Germany on America, represented the American-German churches at the ecclesiastical diet of Frankfort and the Swiss pastoral conference at Basel, and received the degree of D. D. from the university of Berlin. In 1863 he was appointed secretary of the sabbath committee of New York, and removed to that city; and in 1869 he was appointed professor in the Union theological seminary there. From 1867 to 1874 he was acting secretary of the American branch of the evangelical alliance, visiting Europe thrice in the interval; and in 1872 he became president of the American committee of the company of revisers of the English Bible. In August, 1875, he attended at Bonn a conference of Old Catholics, Greeks, and Protestants, held with a view of promoting Christian unity among the churches there represented.

He has published in German "The Sin against the Holy Ghost" (Halle, 1841); "On James and the Brothers of Jesus" (Berlin, 1842); "The Principle of Protestantism" (German and English, Chambersburg, Pa., 1845); "History of the Apostolic Church" (Mercersburg, 1851; 2d ed., Leipsic, 1854; translated into English, New York and Edinburgh, 1853); "German Hymn Book, with a Historical Introduction, Critical and Biographical Notes" (Philadelphia and Berlin, 1859); and "Four Lectures on the Civil War in America, and Overthrow of Slavery" (delivered and published in Berlin, 1865). His works in English are: "What is Church History? A Vindication of the Idea of Historical Development" (Philadelphia, 1846); "St. Augustine, his Life and Labors" (New York, 1853; German, Berlin, 1854); "Ancient Church History" (3 vols., 1853-'68); "America, its Political, Social, and Religious Character," translated from his lectures at Berlin in 1854 (1855); "Germany, its Universities and Divines" (Philadelphia, 1857); "History of the Christian Church of the first three Centuries" (New York and Edinburgh, 1858); "The Moral Character of Christ, or the Perfection of Christ's Humanity a Proof of His Divinity" (1860); "Christ in Song" (1868); "The Vatican Decrees" (1875); and reports of the sabbath committee, 1863-'9, and of the evangelical alliance, 1867-'73. He has now in press (1875) a "History of the Creeds of Christendom," in 3 vols.

From 1848 to 1853 he edited the Kirchenfreund, a German-American monthly, and was for some time co-editor of the "Mercersburg Review;" and he is editor of the American edition of Lange's commentary, to be completed in 27 volumes, of which 18 have appeared (1875).