large block of countries that all had good relations with each other. In the end, in place of a large federation, only a Polish–Romanian alliance was established, beginning in 1921. In comparison, Czechoslovakia had more success with its Little Entente (1920–1938) with Romania and Yugoslavia, supported by France. Piłsudski died in 1935. A later, much reduced version of his concept was attempted by interwar Polish Foreign Minister Józef Beck, a Piłsudski protégé. His proposal, during the late 1930s, of a "Third Europe"—an alliance of Poland, Romania and Hungary—gained little ground before World War II supervened. Beck's Third Europe concept failed to achieve any traction because Germany was the world's second largest economy and all of eastern Europe was dominated economically by the Reich. For economic reasons, there was a tendency in eastern Europe to follow the lead of Berlin rather than Warsaw. Disregarding the 1932 Polish-Soviet Non-Aggression Pact, the Soviet Union allied itself with Nazi Germany to divide Central and Eastern Europe between them. According to some historians, it was the failure to create a strong counterweight to Germany and the Soviet Union, as proposed by Piłsudski, that doomed Intermarium's prospective member countries to their fates in World War II. World War II and since The concept of a "Central [and Eastern] European Union"—a triangular geopolitical entity anchored in the Baltic, Black, and Adriatic or Aegean Seas—was revived during World War II in Władysław Sikorski's Polish Government in Exile. A first step toward its implementation—1942 discussions between the Greek, Yugoslav, Polish and Czechoslovak governments in exile regarding prospective Greek-Yugoslav and Polish-Czechoslovak federations—ultimately foundered on Soviet opposition, which led to Czech hesitation and Allied indifference or hostility. A declaration by the Polish Underground State in that period called for the creation of a Central and Eastern European federal union undominated by any one state. On 12 May 2011, the Visegrád Group countries (Poland, Czech Republic, Slovakia, and Hungary) announced the formation of a Visegrád Battlegroup under Poland's command. The battlegroup was in place by 2016 as an independent force, not part of the NATO command. In addition, starting in 2013, the four countries were to begin joint military exercises under the auspices of the NATO Response Force. Some scholars saw this as a first step toward close Central European regional cooperation. On 6 August 2015, Polish President Andrzej Duda, in his inaugural address, announced plans to build a regional alliance of