portret bezautorski · Public domain

Ran an orphanage in Warsaw built around a children's rights philosophy he set out in a 1919 draft constitution, decades before the idea appeared in international law. When the Nazis forced the orphanage into the Warsaw Ghetto, he moved in with the children rather than accept offers of personal safety, and in 1942 he chose to accompany them to Treblinka, where they were murdered together. He remains a founding figure in the modern idea of children as rights-holders rather than property.