The T4 program murders disabled people and becomes the template for the Holocaust
Gas chambers disguised as showers, first built to kill German patients, are later shipped east to build the death camps
Quick facts
- Program name
- Aktion T4 (named for Tiergartenstrasse 4, Berlin)
- Authorization
- Signed by Hitler autumn 1939, backdated to 1 September 1939
- Gassing facilities
- Bernburg, Brandenburg, Grafeneck, Hadamar, Hartheim, Sonnenstein
- Documented deaths, main phase
- 70,273 (January 1940-August 1941)
- Estimated total deaths, 1939-1945
- At least 250,000
- Legacy
- Gas chamber technology and trained personnel reused at Operation Reinhard camps
What happened
In the autumn of 1939, Adolf Hitler signed a secret authorization, backdated to 1 September 1939 to tie it to the start of the war, extending an existing program of killing disabled infants to adult patients in psychiatric and disability institutions across Germany and Austria. Named Aktion T4 after the Berlin address of its coordinating office, the program built six gassing facilities at Bernburg, Brandenburg, Grafeneck, Hadamar, Hartheim, and Sonnenstein, where victims were killed with bottled carbon monoxide gas in chambers disguised as shower rooms, then cremated. Between January 1940 and August 1941, the program's own internal records show it killed 70,273 institutionalized disabled people. Public knowledge and protests, including from clergy, forced Hitler to formally halt the centralized program in August 1941, but killings of disabled adults and children continued by other methods, chiefly drug overdose and starvation, through the end of the war; the total death toll across all phases is estimated at at least 250,000.
Why it matters
T4 was not a side project. The US Holocaust Memorial Museum's own account states plainly that planners of the Final Solution later reused the gas chambers and crematoria designed for the T4 program to murder Jews, and that T4 personnel who had proven reliable killers went on to staff the Operation Reinhard death camps at Belzec, Sobibor, and Treblinka. The machinery and the men were the same.
How we know
T4's own internal administrative records, which the program kept meticulously to track output, survived the war and give historians an unusually precise victim count for the program's first, centralized phase; the diffuse killing after August 1941 is harder to quantify, which is why the total 250,000 figure is described as an estimate.
Sources
- Holocaust Encyclopedia, US Holocaust Memorial Museum. Euthanasia Program and Aktion T4 · Primary source (author-declared)encyclopedia.ushmm.org · Cited as a "primary" source (no stronger domain match). · Link is live and its text matches the event's key terms (Jul 2026)
- Holocaust Encyclopedia, US Holocaust Memorial Museum. The Murder of People with Disabilities · Primary source (author-declared)encyclopedia.ushmm.org · Cited as a "primary" source (no stronger domain match). · Link is live and its text matches the event's key terms (Jul 2026)
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