This thesis traces the intellectual trajectory of Lorenz Stein (1815-1890), a German legal scholar and political thinker who, despite being a significant theorist during his lifetime, is an obscure figure today, especially in Anglophone scholarship. It focuses on Stein’s writings on socialism and argues that they provide crucial insights into the changing nature of socialist thought in the mid-nineteenth century. It contributes to the project of departing from a Marxist interpretation of the history of socialism that has long been predominant, and uses Stein’s intellectual biography to illustrate how contingent political, cultural and personal factors have shaped both the creation and reception of socialist ideas.