Julius Heinrich Ahrens (14 July 1808 – 2 August 1874) was a German philosopher, jurist, and professor in Brussels, Graz, and Leipzig.
Ahrens, whose main interest was the philosophy of law and the state, was a disciple of Karl Christian Friedrich Krause, with whom he defended his habilitation De confoederatione germanica (Of the German Confederation) in 1830.
After being forced to leave Hanover as a result of his participation in the revolutionary movements there in 1831, he spread the knowledge of Krause's system in France and Belgium through lectures in Paris in 1830 and in Brussels in 1834 and through his extensive writing activity.
[1] In 1848, Ahrens returned to Germany and was sent by the electors of his hometown as a deputy to the Frankfurt parliament.
His works include Cours de droit naturel (Paris 1838), published in German under the title Naturrecht oder Philosophie des Rechts und des Staates (1856, sixth edition Vienna 1870–71), and Juristische Encyklopädie ( 1855–57).