After studying for four years at Copenhagen University, under the Danish philologist Rasmus Christian Rask, he returned to England in 1830, and in 1832 published an English version of Caedmon's metrical paraphrase of portions of the Holy Scriptures, which at once established his reputation as an Anglo-Saxon scholar.
In 1834 he published Analecta Anglo-Saxonica, which was for many years the standard textbook of Anglo-Saxon in English, but his best-known work is a Northern Mythology in three volumes (1851). His was the first complete good translation of the elder Edda (1866).
His other works include:
Thorpe died at Chiswick in July 1870. The value of his work was recognized by the grant to him, in 1835, of a civil list pension.