Christian Karl Josias Bunsen (Korbach 1791 – Bonn 1860; ennobled in 1857) was born to an impoverished family in the principality of Waldeck but managed, by working as a private tutor, to support himself through studies at Göttingen, where Heyne inspired a philological passion in him to complement his initial choice of theology. He eventually obtained his doctorate from Jena University in 1812. By this time, a meeting with Niebuhr had taken his philological interest into a comparative-archeological tradition; he learned a variety of ancient languages, including Persian and Sanskrit (with Silvestre de Sacy, in Paris), before joining Niebuhr on his embassy to Rome as his secretary. Here, he became German language tutor to, and then married, the Welsh heiress Frances Waddington, sister to the future Lady Llanover, in 1817. He succeeded Niebuhr as Prussian ambassador to the Papacy in 1824, and the couple established a salon in Rome which was closely linked to the Nazarenes, and continued his studies of ancient history, establishing contacts with Egyptologists like Champollion and Karl Richard Lepsius, who became a close friend. His Roman residence ended in 1838, when the growing tensions between the Prussian government and the Papacy (especially over mixed-marriage legislation in the predominantly Catholic Prussian Rhineland) made his position untenable; his enforced resignation left him with a strongly anti-Catholic animus. A visit to Britain in 1838-39 saw him, through his sister’s family connections, deeply involved in the fledgeling Cymmreigiddion Society and its Abergavenny eisteddfod. The remarkable international outreach of the 1838 eisteddfod, including contacts with Dwarkanath Tagore and the continental philologist Albert Schulz, are due to Bunsen’s network.

Bunsen, who had gained the sympathy and approbation of the incoming Prussian King Frederick William IV, was appointed ambassador to Britain in 1841, initially with a mission to set up a joint Prussian-Anglican Protestant Bishopric in Jerusalem (a scheme which provoked John Henry Newman’s final conversion to Catholicism). With his combination of theological and antiquarian interests, Bunsen participated actively in the intellectual and social life of his adopted country; his residence as ambassador also marked the heyday of German-English concord. Bunsen was to remain in office until 1854, when he had to resign because of incautious diplomatic manoeuvres during the Crimean War.