Dietrich Bonhoeffer
Two days after Hitler became Chancellor, Bonhoeffer made a radio speech against him. Later, with Martin Niemöller and others, he started the anti-Nazi Confessing Church. Eventually he became part of the attempt by Claus Schenk Graf von Stauffenberg to assassinate Hitler, but was arrested and executed, three weeks before Hitler killed himself. He was hanged days before the liberation of the POW camp where he was imprisoned.