Answer: The Smithsonian Institution
The famed assemblage of museums and research centers came to be thanks to a British scientist named James Smithson. According to the Smithsonian website, "The Smithsonian Institution was established with funds from James Smithson (1765-1829), a British scientist who left his estate to the United States to found “at Washington, under the name of the Smithsonian Institution, an establishment for the increase and diffusion of knowledge.”
Smithson, the illegitimate child of a wealthy Englishman, had traveled much during his life, but had never once set foot on American soil."
It's also noted that "Smithson never wrote about or discussed his bequest with friends or colleagues."