 Post-1991 usage of the term "Eastern Bloc" may be more limited in referring to the states forming the Warsaw Pact (1955–1991) and Mongolia (1924–1992), which are no longer communist states.Sometimes they are more generally referred to as "the countries of Eastern Europe under communism", excluding Mongolia, but including Yugoslavia and Albania which had both split with the Soviet Union by the 1960s.Prior to the common use of the term, in the 1920s "Eastern Bloc" was used to refer to a loose alliance of eastern and central European countries.