[5] During the summer of 1942, after replacing Hauptsturmführer Herbert Lange at Chełmno, Hans Bothmann made substantial changes to the camp's killing methods.

Bothmann's modifications to the execution methods included adding poison to the gasoline used (there is evidence that some red powder and a fluid were delivered from Germany by Maks Sado freight company) in order to kill the prisoners more quickly.

Bothmann was sent to Yugoslavia,[5] but a year later he was summoned back to Poznań in order to supervise the renewed extermination operations at Chełmno,[9] because the Łódź Ghetto continued to take in prisoners not only from occupied Poland but also from Germany, Bohemia, Moravia and other places.

[5] Captured in West Germany by the British, he hanged himself while in custody,[12][13] unaware that a life of freedom might have awaited him, similar to other mass murderers (Strippel,[14] Reinefarth,[15] Fiedler).

He was one of at least a dozen high-profile Nazi German functionaries and Holocaust perpetrators who committed suicide, including Theodor Dannecker ('45), Odilo Globocnik ('45), Richard Glücks ('45), Friedrich Krüger ('45), Ilse Koch ('67), Ernst Grawitz ('45), Karl Jäger ('59), Otto Thierack ('46), Walter Frank ('45), Robert Ley ('45), Manfred von Killinger ('44), and Hans Jeschonnek ('43) among other nationals.