Otto Ambros had a razor-sharp mind. He was cunning and congenial, sly like a fox. He almost always wore a grin. The American war crimes prosecutor Josiah DuBois described him as having a “devilish friendliness” about him. He also had a distracting, rabbitlike habit of sniffing at the air. Ambros was short and heavyset, with white hair and flat feet. He was a brilliant scientist who studied chemistry and agronomy under Nobel Prize winner Richard Willst?tter, a Jew. As a chemist, Ambros had a mind that was capable of pushing science into realms previously unexplored. Few men were as important to IG Farben during the war as Otto Ambros had been.
IG Farben first began producing synthetic rubber in 1935, naming it Buna after its primary component, butadiene. In 1937 Farben presented commercial Buna on the world stage and won the gold medal at the International Expo in Paris. When Germany invaded Poland in September 1939, the Reich’s ability to import natural rubber diminished. Demand for a synthetic alternative skyrocketed, a fact Farben was well aware of in advance of Germany’s attack. Tanks needed treads, aircraft needed tires, and Farben needed to produce rubber. Hitler directed Farben to increase its Buna production further. Dr. Ambros was put in charge and saw to it that Farben opened a second and then a third Buna plant so that supply could meet demand. As the invasion of the Soviet Union was secretly conceived by the German high command, Hitler again called upon Farben’s board of directors to increase its synthetic rubber production. Farben needed to construct a massive new Buna factory. Otto Ambros was put in charge of masterminding this undertaking as well. The place chosen was Auschwitz.
Once, Auschwitz was a regular town. “Ordinary people lived there, and tourists visited to see the castle, the churches, the large medieval market square, and the synagogue,” write historians Debórah Dwork and Robert Jan van Pelt. In the 1930s, visitors sent postcards from the area that read “Greetings from Auschwitz.” When, in the fall of 1940, Otto Ambros pored over maps of this region, called Upper Silesia, in search of a Buna factory site, he found what he was looking for. The production of synthetic rubber required four things: water, flat land, good railway connections, and an abundance of laborers. Auschwitz had all four. Three rivers met in Auschwitz, the Sola, the Vistula, and the Przemsza, with a water flow of 525,000 cubic feet per hour. The land was flat and sixty-five feet above the waterline, making it safe from floodwaters. The railway connections were sound. But most important was the labor issue. The concentration camp next door could provide an endless labor supply because the men were cheap and could be worked to death.
For Farben, the use of slave labor could take the company to levels of economic prowess previously unexplored. First, a financial deal had to be made with the SS. Ambros was instrumental in this act. For months, before the building of the Buna factory got the go-ahead, the SS and Farben haggled over deal points. Some of the paperwork survived the war. On November 8, 1940, the Reich’s minister of economics wrote to Farben’s board of directors, requesting that they hurry up and “settle the question regarding the site.” Otto Ambros lobbied hard for Auschwitz, and in December, IG Farben sent a busload of its rubber experts and construction workers to survey the work site. A Farben employee named Erich Santo was assigned to serve as Otto Ambros’s construction foreman.
“The concentration camp already existing with approximately 7000 prisoners is to be expanded,” Santo noted in his official company report. For Ambros, Farben’s arrangement with the SS regarding slave laborers remained vague; Ambros sought clarity. “It is therefore necessary to open negotiations with the Reich Leader SS [Himmler] as soon as possible in order to discuss necessary measures with him,” Ambros wrote in his official company report. The two men had a decades-old relationship; Heinrich Himmler and Otto Ambros had known one another since grade school. Ambros could make Himmler see eye-to-eye with him on the benefits that Auschwitz offered to both Farben and the SS.
In fact, the SS and IG Farben needed one another. Himmler wanted Farben’s resources at Auschwitz and was eager to make the deal to supply the slaves, so SS officers hosted a dinner party for Farben’s rubber and construction experts at the Auschwitz concentration camp, inside an SS banquet hall there. During the festivities, the remaining issues were finally agreed upon. Farben would pay the SS three reichsmarks a day for each laborer they supplied, which would go into the SS treasury, not to the slaves. “On the occasion of a dinner party given for us by the management of the concentration camp, we furthermore determined all the arrangements relating to the involvement of the really excellent concentration-camp operation in support of the Buna plants,” Ambros wrote to his boss, Fritz Ter Meer, on April 12, 1941. “Our new friendship with the SS is proving very profitable,” Ambros explained.