Mother Teresa, who took in the destitute and gave them a place to die with dignity, was canonised as a saint by Pope Francis in Vatican City on the eve of the 19th anniversary of her death.
Pope Francis said today: "After due deliberation and frequent prayer for divine assistance, and having sought the counsel of many of our brother bishops, we declare and define Blessed Teresa of Calcutta to be a saint and we enrol her among the saints, decreeing that she is to be venerated as such by the whole Church."
The awe and adoration which Mother Teresa inspires was on display in Saint Peter's Square today, where hundreds of thousands of people gathered to celebrate the life of one of the greatest humanitarians of the 20th century.
While 13 heads of state or government attended the ceremony, the official Indian delegation included Foreign Minister Sushma Swaraj, Bengal Chief Minister Mamata Banerjee and Delhi Chief Minister Arvind Kejriwal.
Mother Teresa, who was beatified in 2003, was canonised after the Vatican recognised that she had performed two miracle cures. Her first miracle was curing the stomach cancer of an Indian woman, and the second was healing a Brazilian man, who suffered from several brain tumours.
At the ceremony today, Pope Francis described Mother Teresa as a "tireless worker for mercy."
Born Agnes Gonxha Bojaxhiu into a devout catholic family in 1910 in Skopje, the wizened little Albanian nun became one of the most revered global figures for helping the poor and sick for all her life, even as she courted controversy and criticism for taking a hardline approach on certain catholic beliefs.
In her acceptance speech for the Nobel Peace Prize in 1979, Mother Teresa said, "The poor people are very great people. They can teach us so many beautiful things." "How can you love God whom you do not see, if you do not love your neighbour whom you see, whom you touch, with whom you live," she said.
She had asked that the grand gala dinner be cancelled at the Nobel Peace Prize ceremony and the proceeds be given to the poor of Kolkata.
Two decades after her death at age of 87, thousands of people from all over the world flock to volunteer at the Missionaries of Charity, the Kolkata-based order she founded in 1950 to take care of the less fortunate, which is now run by more than 4,500 nuns in 139 countries.
But Mother Teresa's life and her legacy are not without controversy. In India, Hindu nationalists have accused of her trying to convert those she helped to Christianity, and her opposition to birth control evoked the wrath of feminists such as Germaine Greer who her called a "a religious imperialist."
Indian nationalists have accused her of trying to convert the poor to Christianity and Germaine Greer, the Australian feminist and writer, called her a "religious imperialist" bent on evangelism.
Her most famous critic was late journalist Christopher Hitchens who attacked her in his documentary Hell's Angel in 1994 and then in his essay The Missionary Position, a year later. Hitches called her the "Saint of the Gutters" who propagated "a cult of death and suffering," while taking donations from dictators such as the Duvaliers in Haiti and Enver Hoxha in Albania.
Three years ago, researchers at the University of Montreal said that Mother Teresa was "anything but a saint," glorifying the suffering of the poor rather than relieving it.
The report pointed out her "rather dubious way of caring for the sick, questionable political contacts, her suspicious management of the enormous sums of money she received, and her overly dogmatic views regarding, in particular, abortion, contraception, and divorce."
But none of the criticism and controversy which came her way overshadowed the work she did for the poor. Speaking to ABC News, Joel Hodge, a theologian from the Australian Catholic University, put her influence on par with that of popes John Paul II and John XXIII. "She did really capture the imagination of the world in a way that hardly any other Catholic did," he said.
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