Thomas Pellett (c.1671–1744) was a reluctant medical practitioner, choosing to focus instead on medical study and general learning. He studied medicine at Cambridge University, and later visited Italy with Dr Mead, where he studied for a time at Padua University. After returning to England Pellett became a fellow of the Royal College of Physicians, and became president there between 1735 and 1739. In 1728 Pellett co-edited Sir Isaac Newton's 'Chronology of Ancient Kingdoms' with Martin Folkes.

The portrait was painted in 1737, when Pellett was president of the RCP, by Michael Dahl, a Swedish portrait painter who lived in London for most of his life.