The Medical Missionaries of Mary are a religious institute of the Catholic Church dedicated to providing health care to the underdeveloped regions of the world.
Upon the outbreak of the First World War, Martin joined the Voluntary Aid Detachment, a division of the Red Cross, and helped with the nursing of wounded soldiers.
Agnes Ryan, another initial candidate for the Columban Sisters and by now in her fourth year of medical training, advised Martin that she wished to join her in the African mission.
They arrived prepared to provide medical care, only to learn that they were expected to run a school which had been staffed by French Religious Sisters until two years prior.
To give the parents and children of the school a sense of continuity, the two women were addressed as "Sisters" by the priests and treated as if they were already members of an established religious congregation.
Forced to fill in as Acting Headmistress, Martin determined to confer directly with the bishop in his headquarters at Onitsha, a journey of 100 miles (160 kilometers), for which she brought along three of the oldest girls at the school.
Meeting with the bishop, Martin was advised that caution was needed in providing medical care to the people of her mission, so as not to provoke objections by other missionaries in the region.
[2] In this formal step of forming the new congregation, Martin had encountered the prohibition in the new Code of Canon Law of 1917 of the Catholic Church against members of religious orders practicing medicine.
In 1927 she applied to the monastery of that Order in Dublin, but her application was declined, solely on the decision of the prioress who overrode a unanimous vote by community, feeling that Martin was called to a different path in life.
She then formed a small group of women to provide the domestic service for the preparatory school run by the Benedictine monks of Glenstal Abbey.
[3] While still negotiating to purchase a house in Ireland to serve as a local base there—which complicated by the fact that they were not yet a formal congregation—the small community sailed for Nigeria at the end of 1936.
These are: Ireland, England, Angola, Benin, Kenya, Malawi, Nigeria, Rwanda, South Sudan, Tanzania, Uganda, Brazil, Honduras, Taiwan Taitung and the United States.