Mother Teresa was born in 1910 in war-wracked Albania to Catholic refugees. At the age of 19, she went to India to join the Sisters of Loreto, a missionary order of nuns. She served with the Sisters as a teacher for 20 years. At the age of 38, while traveling by train in India, she had a striking realization that her life's mission was to minister to the poorest of the poor. With the Pope's blessing, Mother Teresa descended into the slums of Calcutta, undoubtedly one of the poorest cities on the planet, and began the Sisters of Charity.