William Thornton was an American architect and physician, best known for his role as the first architect of the United States Capitol. Born in 1759 in British West Indies, he moved to the United States and became involved in various civic projects. Thornton's design for the Capitol was selected in 1793, and he played a significant role in its construction. In addition to his architectural work, Thornton was also a prominent figure in the field of medicine. He earned a medical degree and practiced as a physician while contributing to the development of public health initiatives. His diverse talents made him a notable figure in early American history.