|The Honourable Sir
|Member of the Executive Council and the Legislative Council of Ceylon|
|Born||September 14, 1853|
|Died||9 January 1924(aged 70)|
|Relations||Sir Ponnambalam Ramanathan|
|Children||Sir Arunachalam Mahadeva, Sivananthan Arunachalam and Arunachalam Ramanathan|
|Alma mater||Christ's College, Cambridge,
Royal College, Colombo
His father was Gate Mudaliyar A. Ponnambalam and mother was Sellachchi Ammaiyar. He was the third son of their parents and the younger brother of Sir Ponnambalam Ramanathan who was another famous Ceylon Tamil leader. He was educated at the Colombo Academy (Royal College Colombo), Colombo, and at Christ's College, Cambridge.
He married Swarnambal Namasivayam and had three sons, Sir Arunachalam Mahadeva, KCMG; Sivananthan Arunachalam and Arunachalam Ramanathan. Current Chief Minister of Northern Province, Sri Lanka, C. V. Vigneswaran grandfather was a cousin of P. Ramanathan and P. Arunachalam.
He was one of the first Ceylonese to enter the prestigious Ceylon Civil Service in 1875. He was appointed Registrar General in 1887. He showed his eminence in all the positions he held. His scientific compilation of the National Census Report in 1911 was a masterpiece. The introductory report contains “the most luminous dissertation on the ethnological, social and economic conditions of the Island”. On his retirement from the Public Service in 1913, he was Knighted in recognition of his distinguished service to the country. He was also nominated by the Governor to a seat in the Executive Council.
He was the first Ceylonese to be elected President of the Ceylon Branch of the Royal Asiatic Society. As President of the Saiva Paripalana Sabai he took much interest in Hindu Cultural matters. Along with Sir James Peiris and Sir Marcus Fernando, he was among the first to start agitating for a University for Ceylon (the Hall of residence at the Peradeniya University, formally the Peradeniya campus of University of Ceylon was named Arunachalam Hall, in 1951). He was the Chairman of the Ceylon Reform League. In 1919, Sir P Arunachalam managed to bring the Ceylon Reform League, the Ceylon National Association and the Jaffna Association into a single national organization - the Ceylon National Congress. He died at Madurai on 9 January 1924, while on a pilgrimage worshipping at the Hindu Temples in South India.
- Sketches of Ceylon History; Studies (1906)
- A Digest of the Civil Law of Ceylon, Census Report of 1901.
- A Revel in Bliss (1895).
- A Few Hymns of Manikka Vachaka and Thayumanavar (1897).
- Studies and Translations from the Tamil
- Studies and Translations, Philosophical and Religious (1937)
- "Arunachalam or Arunasalam, Ponnambalam (ARNN871P)". A Cambridge Alumni Database. University of Cambridge.