[1][2] He was the son of Sinnathamby Elisha Rockwood, a customs sub-collector from Alaveddy in northern Ceylon.

[1][3] Rockwood was educated at Vembadi Boys School before being sent to study at Presidency College, Madras from where he matriculated.

[1][2] He then joined Madras Medical College in 1861 on a scholarship, graduating in June 1866 with a first class degree in medicine and surgery.

[2][4] After retirement, Rockwood was appointed to the specially created post of consulting-surgeon of the Colombo General Hospital in 1898.

[2][4] Rockwood was appointed to the Legislative Council of Ceylon in 1898 as the unofficial member representing Tamils, replacing P.