Maximilian Kolbe, Polish Conventual Franciscan friar, volunteered to die in place of a stranger Franciszek Gajowniczek in the German death camp of Auschwitz during WWII. His sacrifice did not go in vain; Gajowniczek survived the war and was later able to reunite with his wife. Kolbe was canonized in 1982 by Pope John Paul II and declared a martyr of charity.