As international law underwent a profound transformation in the twentieth century, two movements in particular led the transformation: the international human rights movement and the movement to unify private law. Both developments challenged the international regime that had predominated since the 1648 Treaty of Westphalia. The human rights movement did so by rejecting the premise that nation-states are the sole actors on the international stage and that international law exists to serve their interests. It posited a contrary set of premises: international law exists to foster the freedom and dignity of the individual, and the international legal system must subject states to accountability in their treatment of individuals, including their own citizens. The Westphalian regime also came under attack from a second source, the unification movement, which was directed at a particular byproduct of the nation-state's rise to dominance: legal fragmentation, exemplified by the creation of national legal codes intended to embody the spirit of particular nation-states rather than their common legal patrimony. These codes moved nearly every country in Europe (with ripple effects on the legal systems of overseas colonies) toward a conception of private law that celebrated particular national characteristics. In the face of this trend, the unification movement of the twentieth century sought to restore not only the unity of European law, but also a conception of law that was less a product of positivism and more an expression of universalism.
Paul R. Dubinsky,
Human Rights Law Meets Private Law Harmonization: The Coming Conflict,
Yale J. Int'l L.
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