The International Congress of Mathematicians (ICM) that was held in Oslo in July 1936 was a unique event that took place in turbulent times, research by Oxford Mathematician Christopher Hollings has revealed. The Nazis had been in power in Germany since 1933, and their dismissal of Jewish scholars from university posts had already had a profound effect on academia the world over. In March 1936, Germany had remilitarised the Rhineland, in violation of the Treaty of Versailles, and sought further to enhance its international standing by hosting the Summer Olympics in August that year. In October 1935, troops from Mussolini’s Italy had invaded Ethiopia (then Abyssinia), to widespread international condemnation, and in the USSR, Stalin was strengthening his grip on power and was about to unleash his Great Terror. All of these events, either directly or indirectly, had their impact on the Oslo ICM.
During the opening speeches of the congress, the spirit of international cooperation was strongly invoked, and yet the participants could not have helped but be aware of the ways in which world politics was affecting their meeting. A number of German mathematicians who might have been expected to attend did not appear since the Nazi authorities had denied them the right to travel. Other mathematicians who had been dismissed from their posts in Germany were a visible presence in Oslo, hoping that they might find jobs elsewhere. Italian mathematicians, on the other hand, were conspicuous by their absence – they too had been denied the right to travel to the congress, in response to Norway’s involvement in the sanctions that had been imposed on Italy by the League of Nations. Soviet mathematicians were also kept at home – many of them were then involved in the so-called ‘Luzin affair’, an ideological attack launched by the Academy of Sciences against the Moscow function theorist N. N. Luzin.
These absences had a noticeable effect in particular on the mathematical profile of the congress: algebraic geometry – then a subject dominated by Italian mathematicians – was entirely absent, whilst the coverage of both probability and topology was rather narrower in scope than originally planned by the organisers, owing to the prominence of Soviet mathematicians in these fields. On the other hand, number theory, hailed by some less-than-neutral commentators as a great German subject at this time, was very strongly represented, accounting for around one third of the plenary lectures.
Two topics that were certainly visible at the Oslo congress were those relating to the award of the Fields Medals. The idea of an international prize in mathematics had first been suggested in the early years of the twentieth century, resulting in the creation of the so-called ‘Guccia Medal’ – but this was awarded only once: to the Italian mathematician Francesco Severi in 1908. The Fields Medals, funded by and named for the Canadian mathematician John Charles Fields, and now presented every four years to researchers under 40, were awarded for the first time at the Oslo congress in 1936: to the American Jesse Douglas and the Finn Lars Ahlfors. The latter received his Medal for work in the theory of functions of a complex variable, whilst Douglas’ award was for his solution of Plateau’s Problem, concerning the existence of a minimal surface for a given boundary – a problem that drew its inspiration from experiments with soap films carried out by the Belgian physicist Joseph Plateau.
A few surviving documents hint at possible intrigue connected with the award of the prize to Douglas. Not all members of the Fields Medal Committee were happy with the way in which the decision-making process had been handled, and there are suggestions that the congress organisers may have tried to suppress a contributed talk that took the study of Plateau’s Problem somewhat beyond Douglas’ work. Whatever the truth of this, the award of these first prizes to two US-based mathematicians signalled the fact that American mathematics had now quite definitely stepped out from beneath the shadow of its European counterpart. The way was paved for the next ICM to be held in the USA – although this didn’t take place until 1950, and then under very different circumstances.
Christopher Hollings is Departmental Lecturer in Mathematics and its History, and Clifford Norton Senior Research Fellow in the History of Mathematics at The Queen’s College, Oxford. Further background to the ICMs can be found in a prior research case study. A detailed account of the Oslo ICM, both mathematical and political, can be found in the book 'Meeting under the Integral Sign? The Oslo Congress of Mathematicians on the Eve of the Second World War' by Christopher Hollings and Reinhard Siegmund-Schultze (American Mathematical Society, 2020).