[2][3] In 2017, the diocese had a population of 6.5 million people, with the main languages spoken being Tamil, Telugu, and Urdu.

It encompasses two civil districts, namely Vellore and Tiruvannamalai, and consists of 84 parishes with a Catholic population of 150,000.

The following chronicles, gathered from various sources, provide historical insight into the Mission, detailing its foundation and development over a span of more than 350 years.

In January 1604, Venkatapathy Deva Rayalu, the last great prince of the declining Vijayanagar empire (now in Andhra Pradesh), conquered the kingdom of Vellore and named it Raya Elluru.

Another conjecture suggests that idols of the Tamil God "Murugan" holding a "Vel" were present in and around Vellore.

The Jesuits, accompanied by their followers, were permitted by the King to rebuild in the area, which is now associated with the Anglican Church.

The Jesuit residences at Chandragiri and Vellore were disbanded by a Royal order of King Philip III of Spain and Portugal in 1611.

Formal Christian faith began to spread in the diocese of Vellore towards the latter part of the 17th century through the efforts of the Madurai Mission.

De La Fontain, Superior of the Carnatic Mission, intervened to halt the persecution carried out by Prince Dewan Hall.

Additionally, 21 villages, where most parishioners lived, were sacked, resulting in numerous Catholic casualties and displacements.

In 1774, when Punganur (Andhra Pradesh) was occupied by Hyder Ali, a group of Telugu Catholics were brought by Fr.

In 1784, the persecution of Tippu Sultan dispersed several Catholic communities from the ancient Carnatic Mission in Rayalaseema.

The Mudali Catholics of Pudur moved of Koratampet and Telugu Reddies and Kavarais settled at Kaniyambady, 12 km South of Vellore.

Moncourrier of the Paris Foreign Missions built a church and presbytery at Adakambarai on land donated by two Catholics.

Subsequently, the church underwent further extensions with the addition of two wings featuring new concrete slab structures.

It was consecrated on 3 January 1988, by Cardinal Duraisamy Simon Lourdusamy, the Prefect of the Congregation for Oriental Churches, during the tenure of Fr.

Archbishops Joseph Morel of Pondicherry (1909–1929) and Mederlet (1928–1934) of Madras played significant roles in the formation of the diocese of Vellore during its initial stages.

In April 1928, the mission of North Arcot with nine parishes, which were under the French Fathers, was consigned by the Holy See to the Salesians of Don Bosco.

Eugene Mederlet, the first Salesian parish priest of Vellore, was made Archbishop of Madras to succeed Bishop Aelen John (1911–1928).

After the death of the Archbishop Mederlet on 12 December 1934, Bishop Louis Mathias was transferred from the See of Shillong to the Archdiocese of Madras, and he took charge of it on 20 July 1935 and governed it till 1965.

The Portuguese had control over coastal areas of Tamil Nadu and Santhome (Mylapore) in the 16th and the first half of the 17th centuries.

The interior of Tamil Nadu was influenced by Mughal ruler Akbar with his friendly attitude to all religions, and similarly by Tirumala Nayak and Queen Mangammal of Madurai and the Kathirava Narasmiah Raj Udayar of Mysore.

The first Portuguese Jesuits were called back by king Philip III due to their scandalous life, and this hindered evangelisation.

The period of Reformation helped to reduce corruption in the Church structures – the clergy, religious and similar organisations.

Darras had taken a vow to build a shrine in honour of Our Lady of Lourdes and built it on a hill top about 2 ½ miles away from Chethupattu.

In 1948 the parish priest, later Bishop of North Arcot, S. David Marianayagam, built the present Hill Chapel to replace the old one.

A. Fernandes, F. Capiaghi, M. Arockiasamy, F. Schlooz, Maria Arul, Peter Mathew, S. Susai and Fr.

In 1955, David Maria Nayagam, Bishop of Vellore Diocese, repaired the Assumption Cathedral and consecrated it.

Blessed Sacrament chapel, prayer meeting hall, Glass paintings of 18 important events of salvific history and 15 mysteries of Rosary, and 165 feet height Belfry are special features of the new cathedral.

[5] In January 2024, Father Roy Lazar from Vellore diocese became the President of the Conference of Diocesan Priests of India (CDPI).