Short answers, pulled from the story.
The International Fantasy Award was an annual literary prize for the best science fiction or fantasy book. From 1951 to 1953 it also recognized the best non-fiction book of interest to science fiction and fantasy readers.
The IFA was judged by an international panel of prominent fans and professionals in the science fiction and fantasy field. This combination of fan enthusiasm and professional standing set it apart from awards voted on by convention attendees alone.
The award was given annually from 1951 to 1955, then skipped 1956 and was presented once more in 1957 before being discontinued.
The Lord of the Rings by J. R. R. Tolkien won the final International Fantasy Award in 1957. It was one of the earliest major recognitions of Tolkien's trilogy by a body of genre fans and professionals.
Willy Ley and Chesley Bonestell won for The Conquest of Space in 1951, Arthur C. Clarke won for The Exploration of Space in 1952, and L. Sprague de Camp and Willy Ley won for Lands Beyond in 1953. The non-fiction category was discontinued after 1953.
George R. Stewart won in 1951 for Earth Abides, John Collier in 1952 for Fancies and Goodnights, Clifford D. Simak in 1953 for City, Theodore Sturgeon in 1954 for More Than Human, Edgar Pangborn in 1955 for A Mirror for Observers, and J. R. R. Tolkien in 1957 for The Lord of the Rings.