Abstract: “First presented in 1936, the Fields Medal quickly became one of mathematicians’ most prestigious, famous, and in some cases notorious prizes. Because its deliberations are confidential, we know very little about the early Fields Medals: how winners were selected, who else was considered, what values and priorities were debated,all these have remained locked in hidden correspondence. Until now. My talk will analyze newly discovered letters from the 1950 and 1958 Fields Medal committees, which I claim demand a significant change to our understanding of the first three decades of medals. I will show, in particular, that the award was not considered a prize for the very best mathematicians, or even for the very best young mathematicians. Debates from those years also shed new light on how the age limit of 40 came about, and what consequences this had for the Medal and for the mathematics profession. These findings also offer a new perspective on the Medal’s role in mathematicians’ international relations in this period. I argue that 1966 was the turning point that set the course for the Fields Medal’s more recent meaning.”