Christoph Wilhelm von Koch (French: Christophe-Guillaume Koch; 9 May 1737 – 25 October 1813, Strasbourg; from 1777 Edler von Koch) was a Protestant diplomat, politician, librarian and writer from Alsace, who also taught constitutional law and history. His pupils included Johann Wolfgang von Goethe, Maximilian von Montgelas, Klemens von Metternich and Louis-Guillaume Otto.
Born in Bouxwiller in Alsace on 9 May 1737, the eighth of eleven children to councillor Johann Reinhard and his wife Susanna Felischmann, he attended the local school there before his parents moved to Strasbourg in 1750, where he spent two years at the protestant school. He then enrolled to study philosophy at the University of Strasbourg. He spent time studying history, encouraged by the teacher Johann Daniel Schöpflin. After three years he transferred to the law department and in June 1759 he graduated as a licenciate in law. In mid-1762 he defended his thesis "De collatione dignitatum et beneficiorum ecclesiasticorum" which had to do with disputes in church law. In the same year he went to Paris where he stayed with his uncle, improved his command of the French language, visited Paris libraries and came in contact with French liberal intellectuals. Many of his later publications were in French.
On returning to Strasbourg he helped Schöpflin to prepare "Alsatia diplomatica", and became assistant to Schöpflin when Andreas Lamey (1726-1802) moved to Mannheim. This was the springboard for Koch's academic career in history and public law. Koch's father had died in 1755 and when Koch's mother also died, in 1767, Koch was taken in as part of the Schöpflin household, where he stayed until Schöpflin's death in 1771. In 1772 he was given a lecturership to the University. In his will, Schöpflin had endowed the city of Strasbourg with his library and Koch also became the librarian. In 1773 Koch was awarded the title of doctor of philosophy for his services to teaching and in 1776 the title of doctor of laws. In 1777, together with his oldest and youngest brothers, he was raised to the peerage by Kaiser Joseph II. He declined a lucrative offer to move to the University of Göttingen. Travelling extensively in Germany, France, Switzerland and the Netherlands, he gained access to libraries and archives and made contact with intellectuals and prominent public figures.