Mother Teresa, who received the Nobel Peace Prize in 1979 for her humanitarian work. Noted for her compassion toward the poor and suffering, Mother Teresa, a diminutive Roman Catholic nun and honorary U.S. citizen, served the sick and destitute of India and the world for nearly 50 years. Her humility and compassion, as well as her respect for the innate worth and dignity of humankind, inspired people of all ages and backgrounds to work on behalf of the world's poorest populations.