Sir Cuthbert Montraville Sebastian GCMG OBE KStJ ED (22 October 1921[1] – 25 March 2017) was the second governor-general of Saint Kitts and Nevis from 1996 to 2013.

He entered Dalhousie University in Halifax, Nova Scotia, where he studied medicine and graduated, in 1958, with a MDCM degree to become a surgeon.

He served in St. Kitts, Nevis and Anguilla as pupil teacher, learner/dispenser, chemist and druggist, laboratory technician, senior dispenser, medical superintendent and obstetrician–gynaecologist.

On 5 July 2002, he received an Honorary Fellowship of the Royal College of Surgeons (FRCS) of Edinburgh in Scotland, for his outstanding career and service to humanity in the field of medicine.

On 3 March 2012 Sebastian welcomed the Earl and Countess of Wessex to St Kitts and Nevis during their visit to the Caribbean as part of Diamond Jubilee of Elizabeth II.