why did congress establish the marshall plan? which nations joined the marshall plan and which nation did not?

Answer 1

Congress established that plan for many reasons.
- To switch from a war economy to a peace economy without a hitch (all the countries who received that aid had to buy American products)
- To stop the spread of communism as it grew on poverty and Europe was totally ruined at that time. Making it wealthy enough people could eat and have a roof and a job was a priority.
- To force those countries to follow US policies (Netherlands was threatened to be cut off if it did not give Indonesia its independence in 1949 + those countries economies were directed by American advisers)
- to get as much of Europe on its side against the USSR

17 countries agreed to receive that help, the USSR was against it and forced its satellite states to refuse (Czechoslovakia had accepted but was forced to refuse by the USSR)

It worked very well as it allowed Europe to recover much more quickly than it would have otherwise (5 years instead of 10 or more), it created a barrier against the USSR , and a lot of it was reimbursed by the countries which had received those loans so the US came back with a positive balance which kick started its peace time economy and allowed it to enter a spending war against the USSR which left the latter ruined and broken.

Countries which joined :
Austria
Belgium
Luxembourg
Denmark
France
Germany (RFA - Edit : West Germany as Bruhaha correctly noted)
Greece
Iceland
Ireland
Italy
Netherlands (with Indonesia)
Norway
Portugal
Sweden
Turkey
UK

And Czechoslovakia which was forced to give it up by the USSR

Edit : Oops, thanks for the RFA correction, Bruhaha

Answer 2

The Marshall plan was suppose to combat the tyrannical behavior of the Soviet Union. John C. Marshall who was Secretary of State under Harry S. Truman, declared this plan in order to grant economic aid to countries resisting communism. This was one of the major policies the U.S enacted to fight the Soviet Union indirectly, including the Truman Doctrine. Basically all the countries formerly with the Allied Powers agreed with the plan. Joined the marshall plan? I dunno what you mean, i think you are referring to the countries benefited from the Marshall plan, there are many, all the countries who were resisting the influence of communism basically agreed to this plan. Which nation did not??? Um the Soviet Union... communist countries.. countries not part of the Marshall plan?

Answer 3

Cabal gave you a good overview, but there were a few omissions from his list. I'll also add a bit of explanation and links to some useful sources.

Two other states to receive Marshall Plan aid:
Switzerland
Free State of Trieste

(The omission of the latter is understandable, since this state only existed from 1947-54... a temporary creation of the peace treaty attempting to resolve tensions between Soviet power in Yugoslavia and Western power {U.S., etc] in Italy -- Trieste is a city-state between these two countries over which there has been contention for many centuries.)

Also, POLAND (like Czechoslovakia) gave a provisional "yes" to the program, but was pressured to decline by the USSR. Other Soviet-bloc nations were pressured never to accept. Finland (bordering the USSR) declined for fear of offending the USSR.

Here is a map of the countries accepting the aid (in which the East-West divide is clear. In the West, only Spain, under Franco, never participated)
http://www.loc.gov/exhibits/marshall/images/wholemap.jpg

For a list of the expenditures for each recipient nation see:
http://en.wikipedia.org/wiki/Marshall_Plan#Expenditures

As for "Germany (RFA)" That refers to what we commonly call "West Germany" as opposed to "East Germany" which was under Soviet control. ("RFA" is the French abbreviation for the country's official name; the usual English abbrevation is be FRG - "Federal Republic of Germany"; the German was BRD, that is, "Bundesrepublik Deutschland". As for the East, that is usually written "Germany DDR" for "Deutsche Demokractische Republik" or English "GDR" - "German Democratic Republic"). Note that West Germany did not become a full participant in the Marshall Plan until 1949, after local government was mostly restored.

____________

A quick overview of the plan, with links to further explanation as well as the original speech by George C. Marshall
http://usinfo.state.gov/products/pubs/marshallplan/index.html

Note that it was NOT just a U.S. aid plan, but involved local contributions. That is key, as one of the principles the Plan was founded on was local co-operation. For a retrospective of the plan and the principles it was based on see:
"The Marshall Plan Then and Now", April, 1967 - Harlan Cleveland (US Permanent representative to NATO)
http://www.trumanlibrary.org/whistlestop/study_collections/marshall/large/documents/index.php?documentdate=1967-04-00&documentid=31&studycollectionid=mp&pagenumber=1&forprinter=true

You might also like to check out info on the exhibit the Library of Congress put out in commemoration of the plan's 50th anniversary:
http://www.loc.gov/exhibits/marshall/mars0.html