L. (Lassa) Oppenheim

Born near Frankfurt am Main on March 30, 1858, Lassa Francis Lawrence Oppenheim was a German jurist who later built an influential academic career in Britain. He taught at Freiburg and Basel before moving to London, and eventually became a professor of international law at Cambridge.

Oppenheim is best remembered for his strong, systematic approach to international law. He argued that international law should be grounded in the actual practice and consent of states, and his two-volume International Law: A Treatise became one of the field’s defining works.

He died in Cambridge on October 7, 1919. Although legal thought has moved on in many ways, Oppenheim is still widely recognized as one of the foundational figures in modern international law.