In 1926, the world came to Wales as Aberystwyth hosted the International Federation of the League of Nations Societies (IFLNS). The congress of 40 countries, originally intended for Dresden in Germany, was relocated and organised in just 3 months as West Wales stepped in to enable the post-WW1 Peace Congress to proceed. The event, organised through David Davies and the Welsh League of Nations Union, was widely praised as an unexpected and unequivocal success - including community activities such as a delegates' pilgrimage to 19th Century peacemaker Henry Richard's memorial in Tregaron.

More info:
https://www.wcia.org.uk/peace-heritage/1926-aberystwyth-peace-congress/