John Coakley Lettsom (1744–1 Nov 1815) was an English physician and philanthropist. He was born on Little Jost Van Dyke in the British Virgin Islands, into one of the early Quaker settlements in the territory, and he grew up to be an abolitionist. His surname is sometimes spelled Lettsome.
Lettsom founded the Medical Society of London in 1773, convinced that a combined membership of physicians, surgeons, and apothecaries would prove productive. His revolutionary idea met with success and the Society has provided a forum for all branches of the medical profession from its inception to the present. Situated at the heart of London's medical community at Lettsome House, Chandos Street, near Cavendish Square, this is the oldest medical society in the United Kingdom.
As founder, president (1775–76, 1784–85, 1808–11, 1813–15), and benefactor Lettsom was the mainstay of the Society from 1773 until his death in 1815.
John Coakley Lettsom was born into the Quaker community on the island of Little Jost Van Dyke in the British Virgin Islands, in 1744. John and his brother were the sole survivors of seven sets of male twins, sons of Edward and Mary Lettsom. John alone was sent to England at the age of six to be educated.
At school in Lancashire the antics of the young Lettsom attracted the attention of the Quaker preacher Samuel Fothergill, who introduced his protégé to his brother, the London physician, Dr John Fothergill. Having completed an apprenticeship to a Yorkshire apothecary, Lettsom came to London in 1766 when, through the influence of Dr Fothergill, he commenced his medical training at St Thomas' Hospital. His studies were interrupted by the death of his father, prompting his return to Tortola in the British Virgin Islands where he freed the slaves he had inherited and provided medical care for the local population. As the only doctor in the islands at that time, he was able to earn a considerable sum. Diligence and industry earned him a fortune, enabling him to resume his studies in Europe. John Coakley Lettsom matriculated at the Leyden University 8 June 1769 He received his Medical Doctor degree 20 Juni 1769. His thesis concerns the natural history of the tea-tree. The title description of his thesis is: Dissertatio inauguralis medica, sistens Observationes ad vires theae pertinentes. Quam … pro gradu Doctoratus summisque in Medicina Honoribus & Privilegiis, ritè ac legitimè consequendis, eruditorum examini submittit Joannes Coakley Lettsom, Tortola – Americanus. Ad diem XX. Junii MDCCLXIX. H.L.Q.S. - Lugduni Batavorum : apud Theodorum Haak, 1769. - 24 p. (interleaved) [3] l. ; 24 cm.