The WPSA was the brain child on one man, Sir Edward Brown, see other articles. The intro to Sir Edward Browns work is also the intro to the WPSA. So Its repeated here.
Later Sir Edward Brown, was one of the first systematic poultry extension teachers and his works were prolific.
Before even the idea of "poultry teachers or extension officers" for the common man was formed, Edward Brown was writing books for the ordinary poultry keeper, researching other countries methods, conducting classes and advocating for a national, and later, an international collaboration of poultry education. He was instrumental in establishing the National Poultry Conference, England, in 1912 then The International Association of Poultry Instructors and Investigators, which became the World Poultry Science Association. The WPSA organized First World Poultry Congress in the Hague. The same sequence of World Poultry Congress meetings continues to this day. It included the two in Australia, 1962 in Sydney, the last to have a live and judged purebreed poultry exhibition as part of the Congress, and the 2008 Congress in Brisbane where again Poultry exhibitors had a range of meetings specific to small breeders and conservationists, though no live poultry. Interestingly the earliest work by Edward Brown was written under a pseudonym, as Edward was concerned that serious scientists were not involved in teaching poultry. Only women did that. I wonder what today's liberated population would think of that. Later he was knighted becoming Sir Edward Brown for his services to the poultry industry.
An interesting comment in his Memoirs, listed below, Sir Edward mentions that he encouraged Herbert Atkinson to write his famous works. Even pure breed game were considered in his mind to be an important part of the gene pool.
So here is a list of materials from the various conferences.
I have been unable to obtain any materials from the 1912 First International Conference, I hope someone could offer some information and pics to include here.
1st 1912
2nd 1924 Barcelona

3rd 1927 Ottowa
4th 1930 London.
The entries, judges and breeders makes great reading.
1933 Italy Some items missing here.

1936 6th Germany The world gets political.

8th 1939 USA Cleveland Ohio.
The judges list isn't readable I will redo but a list of great names.
About 20 x 20mm
the 1945 Congress was cancelled due to WW2.
Eighth 1948 Copenhagen
Ninth 1951 Paris.
10th 1954 Edinburgh Scotland.
Highland show catalogue for the 1954 Congress year and its special binding( modern).
More documents missing
12th 1962 Sydney Australia
Missing the coins struck for the congresss in 1962
1996 New Dehli India
2008 Brisbane Australia
Medallions certificates and provisional documents to add.