Louis Mathias (born 20 July 1887, Paris, died 3 August 1965, Legnano, Italy) was the first Catholic bishop of Shillong who later became the Archbishop of the Roman Catholic Archdiocese of Madras and Mylapore (1935-1952).

The decision was taken in 1927, and the Salesians took over the Immaculate Conception School for Goan boys at Tardeo in 1928.

When this archdiocese was united to the former Propaganda diocese of Mylapore, Mathias became the first Archbishop of Madras-Mylapore.

Together with Archbishop Perier of Calcutta, he was the leading light of the CBCI for many years.

He was also responsible for initiating a nationwide Catholic magazine, The New Leader (earlier The Catholic Leader), and a review for the clergy in India, The Clergy Monthly,[8] now Vidyajyoti: Journal of Theological Reflection.