Smithson died in Genoa, Italy on 27 June 1829. He was buried in Sampierdarena in a Protestant cemetery. In his will written in 1826, Smithson left his fortune to the son of his brother – that is, his nephew, Henry James Dickenson. Dickenson had to change his surname to Hungerford as a condition of receiving the inheritance. In the will Smithson stated that Henry James Hungerford, or Hungerford's children, would receive his inheritance, and that if his nephew did not live, and had no children to receive the fortune, it would be donated to the United States to establish an educational institution to be called the Smithsonian Institution.