Sir William Hamilton KB, PC, FRS (13 December 1730 – 6 April 1803) was a Scottish diplomat, antiquarian, archaeologist and vulcanologist. After a short period as a Member of Parliament, he served as British Ambassador to the Kingdom of Naples from 1764 to 1800. He studied the volcanoes Vesuvius and Etna, becoming a Fellow of the Royal Society and recipient of the Copley Medal.