'That Moral League of Nations against the United States': The Origins of the 1856 Declaration of Paris

The Declaration of Paris, signed by seven European powers on 16 April 1856, is almost forgotten today. Yet it marks the beginning of modern international law as we know it: multilateral treaties open for accession by all powers with the intention of creating new universal rules. Its extension of neutral rights to trade undisturbed in peace-time was a radical reversal of the centuries-old British tradition of extensive belligerent rights. But there is no convincing explanation why Britain signed this treaty and lobbied for its global acceptance. This article shows that the Declaration was a package deal in which Britain accepted broader neutral rights but gained the abolition of privateering. Privateering was no anachronism, but the linchpin of US strategy in case of a conflict with Britain. The Declaration of Paris closed most of the world's ports to privateers and thus ended the practice. The Declaration was also the first multi-lateral law-making treaty and marks the invention of the main instrument we use today to create international law.