Robert de Nobili (1577–1656), an eminent and dedicated Jesuit was the first missionary who visited Salem to spread Christianity and founded Catholic Church there.

After founding a well-known Jesuit mission at Madurai in 1606 AD, he decided to spread the gospel in the neighbouring regions.

In June 1623, he arrived at Senthamangalam, the capital of Ramachandra Nayak, the Vasal of Thirumala Nakak of Madurai.

On 31 July 1626, Nobili received the visit of a Saivist Pandaram and a man belonging to Valluvar caste.

The latter one was impressed by De Nobili's Tamil book, Sign of True Religion, and was himself baptized with the name "Mukthi Udayan" ("Blissful One").

By 1665, there were a large number of Catholics at Kongupatti, Ilupuli, Anaikarapalayam, Omalur, Sankagiri, Anthiyur, Mathiyampatti and Ilanagar.

St. Mary's Co-Cathedral was consecrated in 1975 as 'The Pro Cathedral of Our Lady of Victories' by Bishop Michael Bosco Duraisamy.

This magnificent Cathedral was meticulously planned and carefully constructed with strenuous efforts by late Bishop Most Rev.