Agnes Gonxha Bojaxhiu was born in Skopje in Yugoslavia on August 27, 1910.

Agnes went to a Catholic school and at the age of twelve she knew she wanted to help the poor. When she left school, she decided to train for missionary work. She wanted to work in India.

She left home at eighteen and joined the Sisters of Loreto. The Sisters of Loreto were Irish nuns who had a mission in Calcutta. She trained in Ireland and went to India in 1928. For 19 years she taught at St Mary's High School in Calcutta. She saw many poor people in Calcutta and wanted to help them. In 1946 she left the school to work among the poor in the slums of Calcutta.