
1) Erstwhile alliance 2) Former Eastern Bloc alliance 3) Former Eastern bloc treaty
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https://www.crosswordclues.com/clue/warsaw-pact

Informal name for Warsaw Treaty Organization, a mutual defense organization founded in 1955, including the Soviet Union, Albania (which withdrew in 1961), Bulgaria, Czechoslovakia, the German Democratic Republic (East Germany), Hungary, Poland, and Romania. The Warsaw Pact enabled the Soviet Union to station troops in the countries to its west to o...
Found on
http://soviethistory.msu.edu/glossary/

A 'treaty of friendship, co-operation, and mutual assistance' including the Soviet Union and its satellite states in Central Europe. Signed in 1955, it included eight countries.
Found on
http://www-personal.umich.edu/~alandear/glossary/w.html

treaty establishing a mutual-defense organization (Warsaw Treaty Organization) composed originally of the Soviet Union and Albania, Bulgaria, ... [13 related articles]
Found on
http://www.britannica.com/eb/a-z/w/11

Military defensive alliance 1955-91 between the USSR and East European communist states, originally established as a response to the admission of West Germany into NATO. Its military structures...
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http://www.encyclo.co.uk/local/20688

The USSR''s response to the NATO treaty established a defense-friendship alliance between Albania, Bulgaria, Czechoslovakia, East Germany,Hungary, Poland, Romania and the USSR.
Found on
http://www.pbs.org/pov/myperestroika/glossary/

Political-military alliance founded by the Soviet Union in 1955 as a counterweight to NATO. Members in 1989 included Bulgaria, Czechoslovakia, East Germany, Hungary, Poland, Romania, and the Soviet Union. Served as the Soviet Union's primary mechanism for keeping political and military control over Eastern Europe.
Found on
https://irp.fas.org/world/russia/su_glos.html

Military defensive alliance 1955–91 between the USSR and East European communist states, originally established as a response to the admission of West Germany into NATO. Its military structures and agreements were dismantled early in 1991; a political organization remained until the alliance was officially dissolved in July 1991. The Warsa...
Found on
https://www.encyclo.co.uk/local/21221

In full Warsaw Treaty Organization, a mutual defense organization including the Soviet Union, Albania (which withdrew in 1961), Bulgaria, Czechoslovakia, the German Democratic Republic (East Germany), Hungary, Poland, and Romania. Founded in 1955, it enabled the Soviet Union to station troops in most of the other countries to oppose the forces of t...
Found on
https://www.photius.com/countries/bulgaria/glossary/index.html
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