Allen was born in Northborough, Massachusetts in 1830. He graduated Harvard College in 1851; later he traveled and studied in Europe. A Unitarian, he considered the ministry before deciding to pursue a literary and scholarly career. In 1856, he became assistant principal at the English and Classical School in West Newton, Massachusetts. In 1863-4, during the Civil War, he and his wife, Mary Lambert Allen, ran a school for newly emancipated slaves on the Sea Islands of South Carolina; in 1864-5, he worked as a sanitary agent among black war refugees in Arkansas. After the war, he taught at Antioch College, and in 1867, he became professor of ancient languages and history (afterwards Latin language and Roman history) at the University of Wisconsin–Madison. He died in December 1889.
He wrote prolifically for journals and magazines. His contributions to classical studies chiefly consist of schoolbooks published in the Allen (his brother) and Greenough series. The Slave Songs of the United States (1867), of which he was joint-editor, was inspired by his work among the freedmen and the first book of its kind ever published.
|Wikisource has the text of the 1911 Encyclopædia Britannica article Allen, William Francis.|