Abstract: In contemporary European contract law a patchwork of convergence, harmonization, and unification of commercial laws of contract can be witnessed. Why do certain commercial laws converge or even become unified, whereas others remain separate, national laws? In this paper, two theories from law and economics - namely competition between legal systems and game theory - are applied to nineteenth century European commercial sales law to determine whether or not these concepts can explain the convergence and unification of commercial laws. First, the concepts of convergence by competition and unification by coordination are briefly explained. Second, the convergence of one of the consequences of the seller's non-performance in a trade sale - immediate default upon the lapse of a delivery date - is examined for the legal systems of Prussia, France, and the Netherlands. Third, the convergence of another of the consequences of the seller's non-performance in a trade sale - a choice of remedies upon default - is examined for the jurisdictions within the German Confederation. Game theory is applied to a next step, the unification of German commercial sales law in the Allgemeines Handelsgesetzbuch, to highlight its explanatory force. The paper determines that these two concepts do not exclude but complement one another. Together they provide valuable tools to explain the convergence and unification of contemporary commercial laws. The paper concludes with comments on the future prospects for the convergence and unification of European commercial sales law.
European Review of Private Law