From the United Nations:
On 16 October 1945, 42 countries acted in Quebec, Canada, to create the Food and Agriculture Organization of the United Nations (FAO). In doing so they took another important step forward in man’s perpetual struggle against hunger and malnutrition. For through the establishment of FAO they provided themselves, and the many other nations that were to enter the Organization, with a mechanism through which its Member Countries could deal with a set of problems that are of major concern to all countries and all people… FAO celebrates World Food Day each year on 16 October, the day on which the Organization was founded in 1945.
Read more at Food and Agriculture Organization of the United Nations (FAO).