| Date | Event | From | To |
|---|
| Mission "Sui Iuris" of Karnatic Mission / Pondicherry |
| 1776 | Erected | | Mission "Sui Iuris" of Karnatic Mission / Pondicherry (erected)
|
| Vicariate Apostolic of Pondicherry |
| 1836 | Elevated | Mission "Sui Iuris" of Karnatic Mission / Pondicherry
| Vicariate Apostolic of Pondicherry
|
| Archdiocese of Pondicherry |
| 1 September 1886 | Elevated | Vicariate Apostolic of Pondicherry
| Archdiocese of Pondicherry
|
| 7 June 1887 | Elevated | | Archdiocese of Pondicherry (became a Metropolitan)
|
| 1 September 1899 | Territory Lost | Archdiocese of Pondicherry
| Diocese of Kumbakonam (erected)
|
| 3 July 1928 | Territory Lost | Archdiocese of Pondicherry (North Arcot)
| Archdiocese of Madras
|
| 26 May 1930 | Territory Lost | Diocese of Kumbakonam
Diocese of Mysore
Archdiocese of Pondicherry
| Diocese of Salem (erected) (District of Salem)
|
| 8 February 1951 | Territory Lost | Archdiocese of Pondicherry (Chandernagore)
| Archdiocese of Calcutta
|
| Archdiocese of Pondicherry and Cuddalore |
| 7 August 1953 | Name Changed | Archdiocese of Pondicherry
| Archdiocese of Pondicherry and Cuddalore
|
| 1 September 1969 | Territory Lost | Archdiocese of Pondicherry and Cuddalore (Maduran-takam and Kancheepuram (lower))
| Archdiocese of Madras and Mylapore (Meliapor)
|
| 1 September 1969 | Territory Lost | Archdiocese of Pondicherry and Cuddalore (Tiruvannamalai and Chengam)
| Diocese of Vellore
|