He abandoned the idea of entering the Lutheran ministry, and in 1823 went to Paris, at that time, under Silvestre de Sacy, the major European school of Eastern letters.

From 1826 to 1833 he was nominally professor at Tübingen, but had permission to continue his studies abroad, and passed some years in London and Oxford.

[1] In 1826 he was charged by the French government with the preparation of an edition of the Shahnameh (Livres des Rois) (Book of Kings by Ferdowsi, the Persian epic poet), the first volume of which appeared in 1838, while the seventh and last was left unfinished at his death, being completed by Barbier de Meynard.

His annual reports on Oriental science, presented to the society from 1840 to 1867, and collected after his death under the title Vingt-sept ans d'histoire des études orientales (Paris, 1879), are a history of the progress of Eastern learning during these years.

He also published anonymously, in conjunction with Justus Olshausen (1800–1882), Fragments relatifs à la religion de Zoroastre (Paris, 1829); Confucii Chi-king sive liber carminum, ex latina P. Lacharmi interpretatione (Stuttgart, 1830); and an edition of Y-King, Antiquissimus Sinarum liber, ex interpretatione P. Regis (Stuttgart, 1834–1839).