In the dedication of his great work, De Jure Belli ac Pads, to Louis XIII of France, Grotius addresses the king as “ everywhere known by the name Just no less than that of Louis. . . . Just, when you call back to life laws that are on the verge of burial, and with all your strength set yourself against the trend of an age which is rushing headlong to destruction; . . . when you offer no violence to souls that hold views different from your own in matter of religion; . . . when by the exercise of your authority you lighten the burden of oppressed peoples.”

Two subjects of high importance have recently claimed general attention. Thirty years ago everyone would have said they were settled. Now they are again in the melting-pot. And both concern that all-important matter the freedom of the sea. Both are in dire confusion because assertion has been mistaken for proof.

Strange as it may seem, a coherent theory of expropriation as a separate institution has not been developed in the literature of international law. For the most part only partial aspects of the subject have been treated, and under widely differing categories, e.g., under the general title of “ rights of foreigners,” or “ denial of justice,” or “ international responsibility of states.” But international practice, as embodied in diplomatic and judicial cases, yields sufficient material from which to develop a theory of expropriation as a coherent body of rules of positive international law.

Measures of expropriation and requisition enacted during the Spanish conflict by both the Republican and the Nationalist Governments have given rise to a series of cases which involve fundamental questions relating to state immunity, the effect of the acts of foreign states and governments, and the consequences of de facto recognition. While the decisions in general follow those laid down in similar cases growing out of the Soviet decrees of nationalization, the Spanish Civil War cases contain sufficient elements of novelty to justify their careful study. Both contending parties endeavored by requisition to obtain possession or control of Spanish vessels wherever situate, and the ensuing claims by the owners or the adversary government before foreign courts compelled an examination of the relative status of the de jure government of Spain and of the insurgent government of General Franco during a civil “war” which abounded in anomalous situations.

The awards of October 30, 1939, of the Mixed Claims Commission, United States and Germany, in the sabotage cases, have recently been the subject of litigation in the United States courts. To understand this litigation, it is necessary to complete the history of these cases before the Commission.