[1] Easmon was the only West African to be promoted to Chief Medical Officer and he served in this role with distinction during the last decade of the 19th century.

On both his paternal and maternal lineages, John Easmon was a descendant of Freetown's Founding Families, the Nova Scotian settlers, who were African Americans originally from the United States.

After serving as an apprentice to Dr. Robert Smith at the Colonial Hospital, in 1875 Easmon received his inheritance from the estate of his maternal grandfather and immediately registered at University College London in order to gain Membership of the Royal College of Surgeons (MRCS).

Easmon's distinguished academic career received attention from his uncle, Sir William MacCormac, who offered him a position as an assistant house surgeon.

Easmon was known for wearing the "proper English medical attire" consisting of a silk top hat, frock coat, and striped trousers, which he also wore on his annual leave to England.

Easmon moved to the Gold Coast in 1880 and accepted a position as an Assistant Colonial Surgeon, in addition to opening a private practice in Accra.

He served in this role until his resignation in 1897, following an investigation into whether he maintained a private practice and published articles in the Gold Coast press, in contravention of colonial regulations.