The Mid-European Union was a post-World War I

World War I

World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...

 political association established in the United States of America  on 16 September 1918 "to negotiate territorial disputes between the emerging nations" of Central Europe "and to work towards some form of federal union or economic alliance."

On 26 October 1918, Thomas Masaryk proclaimed the association's Declaration of Common Aims for the independence for the Czecho-Slovaks, Poles

Poles

thumb|right|180px|The state flag of [[Poland]] as used by Polish government and diplomatic authoritiesThe Polish people, or Poles , are a nation indigenous to Poland. They are united by the Polish language, which belongs to the historical Lechitic subgroup of West Slavic languages of Central Europe...

, Yugoslavs

Yugoslavs

Yugoslavs is a national designation used by a minority of South Slavs across the countries of the former Yugoslavia and in the diaspora...

, Ukrainians

Ukrainians

Ukrainians are an East Slavic ethnic group native to Ukraine, which is the sixth-largest nation in Europe. The Constitution of Ukraine applies the term 'Ukrainians' to all its citizens...

, Uhro-Rusyns

Rusyns

Carpatho-Rusyns are a primarily diasporic ethnic group who speak an Eastern Slavic language, or Ukrainian dialect, known as Rusyn. Carpatho-Rusyns descend from a minority of Ruthenians who did not adopt the use of the ethnonym "Ukrainian" in the early twentieth century...

, Lithuanians

Lithuanians

Lithuanians are the Baltic ethnic group native to Lithuania, where they number around 2,765,600 people. Another million or more make up the Lithuanian diaspora, largely found in countries such as the United States, Brazil, Canada, Colombia, Russia, United Kingdom and Ireland. Their native language...

, Romanians

Romanians

The Romanians are an ethnic group native to Romania, who speak Romanian; they are the majority inhabitants of Romania....

, Italian-Irredentists, Unredeemed Greeks

Megali Idea

The Megali Idea was an irredentist concept of Greek nationalism that expressed the goal of establishing a Greek state that would encompass all ethnic Greek-inhabited areas, since large Greek populations after the restoration of Greek independence in 1830 still lived under Ottoman rule.The term...

, Albanians

Albanians

Albanians are a nation and ethnic group native to Albania and neighbouring countries. They speak the Albanian language. More than half of all Albanians live in Albania and Kosovo...

, Zionists, and Armenians

Armenians

Armenian people or Armenians are a nation and ethnic group native to the Armenian Highland.The largest concentration is in Armenia having a nearly-homogeneous population with 97.9% or 3,145,354 being ethnic Armenian....

. This occurred at a meeting in Philadelphia, Pennsylvania

Philadelphia, Pennsylvania

Philadelphia is the largest city in the Commonwealth of Pennsylvania and the county seat of Philadelphia County, with which it is coterminous. The city is located in the Northeastern United States along the Delaware and Schuylkill rivers. It is the fifth-most-populous city in the United States,...

, at Independence Hall

Independence Hall

Independence Hall is the centerpiece of Independence National Historical Park located in Philadelphia, Pennsylvania, United States, on Chestnut Street between 5th and 6th Streets...

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