The history of Shrine Basilica is closely connected with the history of the conversion of the people (Tuticorin), the indigenous people of the Pearl Fishery Coast. In fact, Our Lady of Snows, was fondly called in Portuguese Nossa Senhora das Neves which means Our Lady of Snows. She has been given the unique title of Yelu Kadalthurai, Yega Adikala Thai in Tamil which means the Mother of Refuge for the seven major coastal villages, viz Vembar, Vaippar, Thoothukudi (Snows Basilica, Tuticorin), Punnaikayal, Virapandianpatinam, Thiruchendur and Manapad (Thoothukkudi District).
Once the people of Pearl Fishery Coast had a sharp dispute with the Muslims of this area regarding the right of Pearl Fishing. The Pattankattimar (The leaders of Parava villages) requested the Portuguese to rescue them from the cruelties of the Muslims and the Portuguese agreed on condition of converting to christiantity and the Portuguese routed the Muslims. As a token of gratitude to their redeemers, the Portuguese, the people from about 22 villages numbering about 30,000 embraced Christianity in the year 1535-37. In October 1542, St. Francis Xavier arrived on the shores of the Pearl Fishery Coast to catechize them and strengthen them further in their faith.
Soon there arose a great religious persecution of Madurai who had by this time taken control of the Pearl Fishery Coast. They set fire to churches and houses of Catholics. Hence people left Thoothukudi ( Tuticorin ) and fled to a nearby Island named Raja Theevu (known as Hare-island today). They took along with them the statue of Our Lady of Snows and solemnly installed it in a newly built church there. It was there till the Jesuits returned to Thoothukudi ( Tuticorin ) in 1610. Another tradition says that during the war, the church of Our Lady of Snows at Raja Theevu was destroyed and therefore, the people removed the statue from there and installed it in a small chapel of St. John the Baptist at Sivanthakulam near Thoothukudi ( Tuticorin ). When the Dutch occupied that area, they carried away the statue to a church at Korkai. And it was brought back to Thoothukudi ( Tuticorin ) in 1699.
In 1982, when the Church of Our Lady of Snows celebrated the 400th anniversary, Pope John Paul II raised it to the status of Basilica through his apostolic letter Pervenute illa Dei Beatissimae Genitricis Effigies dated 30 July 1982. It is the greatest honour for a church to be raised to the status of a Basilica. The Greek word Basilica signifies a Royal Hall. In course of time, this word has come to mean a large and beautiful hall. In ancient times, the whole world in general and Rome in particular, erected large halls for administrative purposes. The first hall bearing the name of Basilica existed in Athens. But after the fall of Greeks, the Romans popularised it. It was Julius Caesar who artistically constructed the hall of Basilica Julia for administrative purposes. They are somewhat similar to the Durbar Halls in ancient Indian places. Christ being the king and His Church being His Audience the larger Christian Churches in Rome, came to be called Basilicas. Naturally these Basilicas were large, roomy, bright and ornamental. Today, for a church to be raised to the status of Basilica certain conditions are to be fulfilled: The Church, usually is built with the altar facing the east. Generally it is constructed in one of the classical styles of architecture. It should contain some works of art or house the body of a Saint or a celebrated statue venerated in the land or it should be a place of pilgrimage.