The KWImF was barely three years old when unanticipated difficulties began to create severe problems for the Institute. The first blow to Krehl’s vision for the KWImF came in 1933 with the death of Karl Hausser. Besides the loss to his family and friends, Hausser’s colleagues seriously missed the scientific approach of a man who enthusiastically collaborated with the other KWImF institutes. Perhaps another biologically-minded physicist would have been picked to replace Hausser, but his death was only the first link in a chain of tragic events that began to undermine Krehl’s approach.

The rise of the National Socialists to political power three years after the establishment of the institute severely hampered development of the KWImF. Indeed, it damaged the entire country’s scientific infrastructure. In 1933, a wave of Jewish scientists, “sympathizers” and “political radicals” were immediately removed from university positions throughout the country. With the writing literally on the wall, a number of important KWImF assistants and students also packed their bags and departed. It has been estimated that thirty percent of the nation’s scientists fled Germany during the 1930s. Within the space of seven years, the country was transformed from the virtual center of the scientific world to an isolated island.

Ironically, the KWG’s attempts to create a safe haven from National Socialist abuses contributed to the dismantling of Krehl’s dream at KWImF. The emergency appointment of Walther Bothe to replace Karl Hausser was precipitated by the political turmoil and ideological purges that took place at the University of Heidelberg. Given the circumstances and Planck‘s personal request to Krehl, the appointment of a nuclear physicist to the post was understandable because it kept a world class scientist in the country. Yet this emergency measure came with a prize, for Bothe had little interest in collaborating with fellow KWImF directors Krehl, Meyerhof or Kuhn. Krehl understood this when he granted Planck’s request, although he knew the scientific consequences and privately held out hope that Bothe would refuse the offer.

Problems arose almost immediately. For example, Bothe was asked to absorb into his Physics Institute the small research group of Isolde Hausser, the former KWImF director’s widow. While Isolde Hausser was a physicist of standing (she and Lise Meitner were the only full female members elected to the Kaiser Wilhelm Society), her research was in an entirely different field than Bothe’s. Moreover, she was strongly attached to both her husband’s intellectual legacy and Krehl’s original principle for the KWImF. Unfortunately, rather than consider her as a fellow colleague in physics, Bothe resented her presence, considering her a burden, who drained funds and used laboratory space needed by his own research group. Isolde Hausser soon became a pawn in internal squabbles that were to develop between Bothe and Richard Kuhn.

Meanwhile, Otto Meyerhof was facing problems of his own. As early as June of 1933, the local Nazi party began agitating for his removal from the KWImF. They were particularly affronted by the principle of annually rotating the administrative directorship between the heads of the four different research institutes. They considered it intolerable that a Jew might hold this prestigious title. Initially, Kaiser Wilhelm Society President Max Planck, Administrative Director Friedrich Glum and Krehl simply ignored the letters and calls of the Nazi officials. But frustrated by the lack of response to their demands, the  local party leaders eventually called upon high level government officials to pressure the Kaiser Wilhelm Society. For a long period, the society’s non-governmental status and liberal leadership kept the Nazis at arms length, but it was not able to do so forever.

Professionally, this turmoil could not have come at a worse time for Meyerhof. He and Lohmann were just sorting out the significance of ATP and a flood of other results were pouring in at the Physiology Institute. Meyerhof’s long-standing goal of solving the puzzles of muscle contraction and glycolysis were tantalizingly within reach. Although he had briefly considered emigrating in 1933, leaving would have meant saying good-bye to an outstanding group of assistants and abandoning his superbly equipped laboratory. In the midst of an economic depression, he knew that replicating those conditions elsewhere would be difficult. Meyerhof therefore chose to remain in Germany.

By 1935, KWImF relationships with the University of Heidelberg were rapidly disintegrating. Initially, the University had thrown its full support behind the KWImF, awarded honorary professorships to each of the directors, provided the KWImF with students, awarded Ph.D.s and habilitated its scientific assistants. The seeds of tension, however, had begun to incubate soon afterward. Many academics were resentful of the strong financial backing of the KWImF and the fact that its scientists had no teaching obligations. Instead of a catalyst for further scientific investment in the region, many faculty members feared that the KWImF was siphoning off human and material resources that might have gone to the university system. With the growing influence of the National Socialist movement at the University of Heidelberg, the presence of Meyerhof and Bothe only exacerbated this tension. Moreover, the KWImF had taken in a number of “non-desirable” students who had been forced out during the university purges. By the end of the decade, even Kuhn had problems obtaining students from the university, and assistants found it necessary to habilitate at other institutions far from Heidelberg.

Rather than disappearing quickly, as many Germans had told themselves, the Nazis gradually broadened their political power base and it became increasingly difficult for the KWG and KWImF to resist interference. One early concession kept Meyerhof from reclaiming the rotating administrative directorship of the KWImF. Initially, this did not appear to present serious problems. Meyerhof knew from practical experience that the job was an administrative burden, with little impact on scientific decisions. Secondly, Krehl agreed to take over the position until the political situation settled down. As the KWImF’s senior scientist and founder, this solution was internally acceptable and gave the local fascist leaders the symbolic victory they required. Ironically, it was probably Krehl who suffered most from this decision, because it meant less time for him to organize his own struggling Pathology Institute.

Unfortunately, not long after the Meyerhof compromise appeared to stabilize the external political situation, Krehl fell ill and was unable to attend to his professional duties. Richard Kuhn quietly took over most of the mundane administrative duties as a favor to Krehl. Because Bothe and Meyerhof were preoccupied with some of the most productive work of their careers, no one openly questioned Kuhn’s motives.

The death of Krehl in the summer of 1937, however, had several important ramifications. Krehl’s own Pathology Institute, which had been delayed so often during financial and political crises, was far behind in its development compared to the other three research groups. It was now in disarray and yet another high level search would have to be made to replace Krehl. More importantly, the symbolic loss of leadership created a ripple effect throughout the KWImF. Krehl had always been the philosophical driving force behind the KWImF’s collaborative ideal. His death now moved the political question of who should lead the KWImF back to the forefront.

As far as the KWG administration and senate were concerned, Kuhn was the obvious choice to replace Krehl. Given the risk of confrontation with the National Socialists, Meyerhof was clearly out of consideration as a candidate and, although he was more than ten years older than Kuhn, Bothe had only been at the KWImF for three years and his physics research was unrelated to Krehl’s original principle. Besides, Kuhn’s scientific star was on the rise and he was already on the job informally and performing admirably. In October of 1937, the KWG nominated Kuhn for the permanent directorship of the KWImF and he was elected in the KWG senate with 21 of 28 votes.

This vote in the KWG senate, however, came as a complete surprise to Bothe. He was livid and fired off a formal protest to Glum and new KWG President Carl Bosch. Because the original decision to abandon the rotation principle had been made to deal with the “Meyerhof problem,” Bothe insisted that some sort of rotation rule must be put back in force. In fact, legally speaking, Bothe was correct; the KWImF by-laws had never been changed. Furthermore, as ten years Kuhn’s senior, he had some grounds to consider himself more qualified as a permanent director. More revealingly, Bothe accused Kuhn of taking over the de facto leadership of the KWImF without consulting his colleagues in Heidelberg and then shrewdly positioning himself with the KWG administration to obtain the official post. As far as Bothe was concerned, this was typical behind-the-back maneuvering by  Kuhn.

Whether Kuhn consciously maneuvered himself into position at Bothe’s expense is difficult to fully assess. Bothe was an extremely sensitive man, and easily slighted. Glum and Bosch tried to explain the logic of their choice and smooth Bothe’s ruffled feathers, encouraging him to work cooperatively with Kuhn. But Bothe ignored these requests. On the other hand, Kuhn was extremely ambitious and during the coming years he would gain a reputation in many quarters for working behind the scenes to attain his goals. Both men were rather proud, with high opinions of themselves. And each inspired tremendous loyalty within his own research group, thus helping to perpetuate two very different versions of this story. As often is the case, the truth probably lies somewhere in between. In any event, Bothe never forgave Kuhn. Although they both maintained a stance of professional respect for each other’s scientific accomplishments, the two rarely talked to one another afterwards.

While these administrative problems developed, Meyerhof’s situation had gradually gone from uncomfortable to precarious. In 1937, he began making secret plans to leave Germany. Writing in code, his former assistant David Nachmansohn arranged for a position in France for his old professor. In 1938, Meyerhof and his family made their way first to Switzerland, then on to Paris. After the occupation of France by Germany,  they fled once more, eventually arriving in Philadelphia in the USA, where Meyerhof worked until his death in 1951.

Meyerhof’s departure was hardly a complete surprise, nor resented by the assistants he left behind. It did, however, create obvious problems for the remaining members of his institute. Would they be retained or released outright? Without formal resignation from Meyerhof, what were the procedures for dismantling the Physiology Institute or, alternatively, replacing Meyerhof?

With Meyerhof and Krehl gone, Kuhn now appointed himself permanent director of the KWImF, taking firm control of scientific policy of the overall institute. He had, for example, a primary influence on the selection of scientists who were recruited to replace Krehl and Meyerhof. The bacteriologist Gerhard Domagk was asked to take over the Pathology Department. Kuhn also strongly advocated the appointment of Hermann Rein, a cardiovascular physiologist, to fill in Meyerhof’s position. The research of both of these candidates clearly complemented the new research directions of Kuhn’s own work, but their recruitment only underscored the rift between Kuhn and Bothe.

Rein visited the KWImF in October of 1938, on the verge of accepting the position. But the approaching cloud of war undermined the negotiations and the KWG decided to postpone any decisions on the Domagk and Rein appointments until the political situation in Germany stabilized. It would be a unexpectedly long wait.

At the end of the decade, many of the scientists at the KWImF still clung to the hope that war might be avoided. However, by 1939, isolation in the ivory tower of the KWImF was no longer realistic. Clearly, the German government had prepared itself well during the late 1930s for the coming conflict – militarily, economically and symbolically. The value of research institute’s like the KWImF had been taken into account. For example, even before the war had begun, Bothe and his assistants were drafted into the Uranverein, a group of the country’s top physicists, who were assigned the task of investigating the development of atomic energy for the military purposes. After the invasion of Poland, the government took firm control of policy that had previously existed exclusively in the hands of the KWG administration and the scientists at the KWImF.

Even good news seemed to be tainted. On November 17, 1939, for example, it was belatedly announced that Richard Kuhn had won the 1938 Nobel Prize for Chemistry. That evening there was a great celebration at the Chemical Institute in honor of Kuhn. Clearly, sharing the official announcement with his colleagues and students at the KWImF was moment of great pride for Kuhn.

Kuhn’s sense of jubilation about the coveted award was, however, swiftly brought into check. As it turned out, awards for 1939 Nobel Prizes to the German scientists Gerhard Domagk and Adolf Butenandt had been announced at the same time as Kuhn’s award. When Domagk sent a letter to the Nobel Committee thanking them for the award, the note was intercepted by the Gestapo and all three Prize winners were immediately summoned to Berlin.

One might assume that such a prize represented an opportunity for National Socialists to promote their Aryan agenda, but after the 1935 Nobel Peace Prize had been awarded to Carl von Ossietzky, a vocal political opponent who had been interned in a concentration camp, Hitler had raged against the Nobel Committee. Instead of exploiting this powerful symbol of scientific excellence, all three Nobel Laureates were told that acceptance of the Prizes would not be in the best interest of the country. Kuhn, Domagk and Butenandt subsequently sent formal notices to Sweden turning down their awards.

This was clearly a bitter pill for Kuhn to swallow, for it was known that winning the Nobel had been a goal since days as a student. He was not prepared, however, to challenge directives of the Research Ministry backed by the Gestapo.

By the end of 1939, only two of the original KWImF research institutes remained and their directors were not speaking. The Pathology and Physiology Institutes lay empty. Collaboration was a distant memory. Moreover, a corrupt  government began to dictate research policy. Krehl’s idealistic dream of a multidisciplinary institute dedicated to medical and biological research appeared to lay in ruins.

The work of both Bothe and Kuhn would be dramatically curtailed by the war and postwar turmoil. A return to similar levels of scientific accomplishment would only occur after the reformation of the KWImF as the Max Planck Institute for Medical Research in 1948 and influx of funding associated with the German economic miracle of the 1950s. By the 1960s, the vacant institutes were refilled, and chemistry, biophysics, physiology and the new field of molecular biology were united at the MPImF to reestablish the institute’s world-class reputation.