In 1950 she received Vatican approval to found a new religious congregation, the Missionaries of Charity, dedicated to what its constitution called wholehearted service to the poorest of the poor. What began as a single small community in Calcutta grew, over the following decades, into a congregation with houses in more than a hundred countries, running hospices, orphanages, clinics and shelters, and Mother Teresa herself became one of the most publicly recognized religious figures of the twentieth century, awarded the Nobel Peace Prize in 1979 for that work.
She died in Calcutta on 5 September 1997. Pope John Paul II beatified her in 2003 and Pope Francis canonized her in 2016 as Saint Teresa of Calcutta, one of the fastest canonizations in modern Catholic history. Her posthumously published private letters revealed decades of profound spiritual doubt and a felt absence of God that stood in stark contrast to her public image, a disclosure that reshaped how scholars and believers alike have since read her life and work. The congregation's work expanded well beyond Calcutta during her lifetime to include homes for the dying, leprosy treatment centers, orphanages and, later, hospices for those with HIV and AIDS, and it continued to grow after her death under successive superiors general, still following the constitution she had established in 1950.