The Treaty of Trianon, signed on June 4, 1920, destroyed a kingdom that had existed for a thousand years by allotting two thirds of the territory and population of the historic realm to Czechoslovakia, Rumania, Jugoslavia, and Austria. Before the collapse of the Central Empires Hungary had a population of about twenty-two millions, nearly half of whom were Hungarian. After the treaty the population was reduced to seven and a half millions, in the proportion: Hungarian, 88.4 per cent; German, 7; Slovakian, 2.2; and about 110,000 Croatians, Rumanians, and Serbians. In order to accomplish the liberation of subject nationalities, Hungarians were put under foreign yoke, all (with the exception of part of those given to Rumania) in contiguous territories, as follows: Subject to Czechoslovakia 1,084,000 Subject to Rumania 1,705,000 Subject to Jugoslavia 458,000 Subject to Austria 80,000 The Paris Conference, on the recommendation of military experts, changed the boundary between Austria and Hungary, south of the Danube, in order to protect Pressburg (Bratislava), given to Czechoslovakia for a port. There was the added motive of creating a breach between the former allies. The large number of Hungarians put under Czechoslovakia was due to two considerations: to afford the new state a long Danube frontier; and to make possible an Entente airplane and military base close to the capital of Hungary. An ethnographic frontier with Rumania was rejected because of the promises to Rumania during the war to induce her to intervene on the side of the Entente Powers. The Czechoslovak frontier was carried across the Carpathians to include Ruthenia, and nearly half a million Hungarians were transferred to Jugoslav nationality, so that Czechoslovakia, Rumania, and Jugoslavia might have common frontiers and railway communications in friendly territory. The Entente Powers had fought to liberate subject races, not simply to give border populations a change of masters. But the new countries needed strategic frontiers and economic resources. Therefore their liberation necessitated the slavery of one third of the former master race to the former subject races. Defeated Hungary saw the principle of self-determination invoked in behalf of other peoples for the purpose of despoiling her, but ignored when for economic or strategic reasons the liberated peoples needed territories inhabited by Hungarians. It was a case of turning the tables. Might once more made right. The Hungarians were given a dose of their own medicine. The outcry against the Treaty of Trianon, whose terms were announced just after Hungary had passed through the Bela Kun Communist reign of terror and the occupation and pillage of Budapest by the Rumanians, was universal. But the vanquished Magyars were as powerless to protest effectively against the Treaty of Trianon as the Germans had been a year earlier to reject the Treaty of Versailles.